33.E: Special Relativity (Exercise)
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Conceptual Questions
33.3: Accelerators Create Matter from Energy
1. The total energy in the beam of an accelerator is far greater than the energy of the individual beam particles. Why isn’t this total energy available to create a single extremely massive particle?
2. Synchrotron radiation takes energy from an accelerator beam and is related to acceleration. Why would you expect the problem to be more severe for electron accelerators than proton accelerators?
3. What two major limitations prevent us from building high-energy accelerators that are physically small?
4. What are the advantages of colliding-beam accelerators? What are the disadvantages?
33.4: Particles, Patterns, and Conservation Laws
5. Large quantities of antimatter isolated from normal matter should behave exactly like normal matter. An antiatom, for example, composed of positrons, antiprotons, and antineutrons should have the same atomic spectrum as its matter counterpart. Would you be able to tell it is antimatter by its emission of antiphotons? Explain briefly.
6. Massless particles are not only neutral, they are chargeless (unlike the neutron). Why is this so?
7. Massless particles must travel at the speed of light, while others cannot reach this speed. Why are all massless particles stable? If evidence is found that neutrinos spontaneously decay into other particles, would this imply they have mass?
8. When a star erupts in a supernova explosion, huge numbers of electron neutrinos are formed in nuclear reactions. Such neutrinos from the 1987A supernova in the relatively nearby Magellanic Cloud were observed within hours of the initial brightening, indicating they traveled to earth at approximately the speed of light. Explain how this data can be used to set an upper limit on the mass of the neutrino, noting that if the mass is small the neutrinos could travel very close to the speed of light and have a reasonable energy (on the order of MeV).
9. Theorists have had spectacular success in predicting previously unknown particles.
10. What lifetime do you expect for an antineutron isolated from normal matter?
11. Why does the \(\displaystyle η^0\) meson have such a short lifetime compared to most other mesons?
12. (a) Is a hadron always a baryon?
(b) Is a baryon always a hadron?
(c) Can an unstable baryon decay into a meson, leaving no other baryon?
13. Explain how conservation of baryon number is responsible for conservation of total atomic mass (total number of nucleons) in nuclear decay and reactions.
33.5: Quarks: Is That All There Is?
14. The quark flavor change \(\displaystyle d→u\) takes place in \(\displaystyle β^−\) decay. Does this mean that the reverse quark flavor change \(\displaystyle u→d\) takes place in \(\displaystyle β^+\) decay? Justify your response by writing the decay in terms of the quark constituents, noting that it looks as if a proton is converted into a neutron in β+ decay.
15. Explain how the weak force can change strangeness by changing quark flavor.
16. Beta decay is caused by the weak force, as are all reactions in which strangeness changes. Does this imply that the weak force can change quark flavor? Explain.
17. Why is it easier to see the properties of the c, b , and t quarks in mesons having composition \(\displaystyle W^−\) or \(\displaystyle t\bar{t}\) rather than in baryons having a mixture of quarks, such as \(\displaystyle udb\)?
18. How can quarks, which are fermions, combine to form bosons? Why must an even number combine to form a boson? Give one example by stating the quark substructure of a boson.
19. What evidence is cited to support the contention that the gluon force between quarks is greater than the strong nuclear force between hadrons? How is this related to color? Is it also related to quark confinement?
20. Discuss how we know that \(\displaystyle π-mesons (π^+,π,π^0)\) are not fundamental particles and are not the basic carriers of the strong force.
21. An antibaryon has three antiquarks with colors \(\displaystyle \bar{R}\bar{G}\bar{B}\). What is its color?
22. Suppose leptons are created in a reaction. Does this imply the weak force is acting? (for example, consider \(\displaystyle β\) decay.)
23. How can the lifetime of a particle indicate that its decay is caused by the strong nuclear force? How can a change in strangeness imply which force is responsible for a reaction? What does a change in quark flavor imply about the force that is responsible?
24. (a) Do all particles having strangeness also have at least one strange quark in them?
(b) Do all hadrons with a strange quark also have nonzero strangeness?
25. The sigma-zero particle decays mostly via the reaction \(\displaystyle \sum{}^0→Λ^0+γ\). Explain how this decay and the respective quark compositions imply that the \(\displaystyle \sum{}^0\) is an excited state of the \(\displaystyle Λ^0\).
26. What do the quark compositions and other quantum numbers imply about the relationships between the \(\displaystyle Δ^+\) and the proton? The \(\displaystyle Δ^0\) and the neutron?
27. Discuss the similarities and differences between the photon and the \(\displaystyle Z^0\) in terms of particle properties, including forces felt.
28. Identify evidence for electroweak unification.
29. The quarks in a particle are confined, meaning individual quarks cannot be directly observed. Are gluons confined as well? Explain
33.6: Grand Unified Theories
30. If a GUT is proven, and the four forces are unified, it will still be correct to say that the orbit of the moon is determined by the gravitational force. Explain why.
31. If the Higgs boson is discovered and found to have mass, will it be considered the ultimate carrier of the weak force? Explain your response.
32. Gluons and the photon are massless. Does this imply that the \(\displaystyle W^+, W^−\), and \(\displaystyle Z^0\) are the ultimate carriers of the weak force?
Problems & Exercises
33.1: The Yukawa Particle and the Heisenberg Uncertainty Principle Revisited
33. A virtual particle having an approximate mass of \(\displaystyle 10^{14}GeV/c^2\) may be associated with the unification of the strong and electroweak forces. For what length of time could this virtual particle exist (in temporary violation of the conservation of mass-energy as allowed by the Heisenberg uncertainty principle)?
Solution
\(\displaystyle 3×10^{−39}s\)
34. Calculate the mass in \(\displaystyle GeV/c^2\) of a virtual carrier particle that has a range limited to \(\displaystyle 10^{−30}\) m by the Heisenberg uncertainty principle. Such a particle might be involved in the unification of the strong and electroweak forces.
35. Another component of the strong nuclear force is transmitted by the exchange of virtual K-mesons. Taking K-mesons to have an average mass of \(\displaystyle 495MeV/c^2\), what is the approximate range of this component of the strong force?
Solution
\(\displaystyle 1.99×10^{−16}m(0.2fm)\)
33.2: The Four Basic Forces
36. (a) Find the ratio of the strengths of the weak and electromagnetic forces under ordinary circumstances.
(b) What does that ratio become under circumstances in which the forces are unified?
Solution
(a) \(\displaystyle 10^{−11}\) to 1, weak to EM
(b) 1 to 1
37. The ratio of the strong to the weak force and the ratio of the strong force to the electromagnetic force become 1 under circumstances where they are unified. What are the ratios of the strong force to those two forces under normal circumstances?
33.3: Accelerators Create Matter from Energy
38. At full energy, protons in the 2.00-km-diameter Fermilab synchrotron travel at nearly the speed of light, since their energy is about 1000 times their rest mass energy.
(a) How long does it take for a proton to complete one trip around?
(b) How many times per second will it pass through the target area?
Solution
(a) \(\displaystyle 2.09×10^{−5}s\)
(b) \(\displaystyle 4.77×10^4Hz\)
39. Suppose a \(\displaystyle W^−\) created in a bubble chamber lives for \(\displaystyle 5.00×10^{−25}s\). What distance does it move in this time if it is traveling at 0.900 c? Since this distance is too short to make a track, the presence of the \(\displaystyle W^−\) must be inferred from its decay products. Note that the time is longer than the given \(\displaystyle W^−\) lifetime, which can be due to the statistical nature of decay or time dilation.
40. What length track does a \(\displaystyle π^+\) traveling at 0.100 c leave in a bubble chamber if it is created there and lives for \(\displaystyle 2.60×10^{−8}s\)? (Those moving faster or living longer may escape the detector before decaying.)
Solution
78.0 cm
41. The 3.20-km-long SLAC produces a beam of 50.0-GeV electrons. If there are 15,000 accelerating tubes, what average voltage must be across the gaps between them to achieve this energy?
42. Because of energy loss due to synchrotron radiation in the LHC at CERN, only 5.00 MeV is added to the energy of each proton during each revolution around the main ring. How many revolutions are needed to produce 7.00-TeV (7000 GeV) protons, if they are injected with an initial energy of 8.00 GeV?
Solution
\(\displaystyle 1.40×10^6\)
43. A proton and an antiproton collide head-on, with each having a kinetic energy of 7.00 TeV (such as in the LHC at CERN). How much collision energy is available, taking into account the annihilation of the two masses? (Note that this is not significantly greater than the extremely relativistic kinetic energy.)
44. When an electron and positron collide at the SLAC facility, they each have 50.0 GeV kinetic energies. What is the total collision energy available, taking into account the annihilation energy? Note that the annihilation energy is insignificant, because the electrons are highly relativistic.
Solution
100 GeV
33.4: Particles, Patterns, and Conservation Laws
45. The π0 is its own antiparticle and decays in the following manner: \(\displaystyle π^0→γ+γ\). What is the energy of each \(\displaystyle γ\) ray if the \(\displaystyle π^0\) is at rest when it decays?
Solution
67.5 MeV
46. The primary decay mode for the negative pion is \(\displaystyle π^−→μ^−+\bar{ν_μ}\). What is the energy release in MeV in this decay?
47. The mass of a theoretical particle that may be associated with the unification of the electroweak and strong forces is 1014GeV/c2.
(a) How many proton masses is this?
(b) How many electron masses is this? (This indicates how extremely relativistic the accelerator would have to be in order to make the particle, and how large the relativistic quantity \(\displaystyle γ\) would have to be.)
Solution
(a) \(\displaystyle 1×10^{14}\)
(b) \(\displaystyle 2×10^{17}\)
48. The decay mode of the negative muon is \(\displaystyle μ^−→e^−+\bar{ν_e}+ν_μ\).
(a) Find the energy released in MeV.
(b) Verify that charge and lepton family numbers are conserved.
49. The decay mode of the positive tau is \(\displaystyle τ^+→μ^++ν_μ+\bar{ν_τ}\).
(a) What energy is released?
(b) Verify that charge and lepton family numbers are conserved.
(c) The \(\displaystyle τ^+\) is the antiparticle of the \(\displaystyle τ^−\).Verify that all the decay products of the \(\displaystyle τ^+\) are the antiparticles of those in the decay of the \(\displaystyle τ^−\) given in the text.
Solution
(a) 1671 MeV
(b) \(\displaystyle Q=1,Q'=1+0+0=1.L_τ=−1;L'τ=−1;Lμ=0;L'μ=−1+1=0\)
(c) \(\displaystyle τ^−→μ^−+v_μ+\bar{v_τ}⇒μ^−\) antiparticle of \(\displaystyle μ^+; v_μ\) of \(\displaystyle \bar{v_μ}; \bar{v_τ}\) of \(\displaystyle v_τ\)
50. The principal decay mode of the sigma zero is \(\displaystyle \sum{}^0→Λ^0+γ\).
(a) What energy is released?
(b) Considering the quark structure of the two baryons, does it appear that the \(\displaystyle \sum{}^0\) is an excited state of the \(\displaystyle Λ^0\)?
(c) Verify that strangeness, charge, and baryon number are conserved in the decay.
(d) Considering the preceding and the short lifetime, can the weak force be responsible? State why or why not.
51. (a) What is the uncertainty in the energy released in the decay of a \(\displaystyle π^0\) due to its short lifetime?
(b) What fraction of the decay energy is this, noting that the decay mode is \(\displaystyle π^0→γ+γ\) (so that all the \(\displaystyle π^0\) mass is destroyed)?
Solution
(a) 3.9 eV
(b) \(\displaystyle 2.9×10^{−8}\)
52. (a) What is the uncertainty in the energy released in the decay of a \(\displaystyle τ^−\) due to its short lifetime?
(b) Is the uncertainty in this energy greater than or less than the uncertainty in the mass of the tau neutrino? Discuss the source of the uncertainty.
33.5: Quarks: Is That All There Is?
53. (a) Verify from its quark composition that the \(\displaystyle Δ^+\) particle could be an excited state of the proton.
(b) There is a spread of about 100 MeV in the decay energy of the \(\displaystyle Δ^+\), interpreted as uncertainty due to its short lifetime. What is its approximate lifetime?
(c) Does its decay proceed via the strong or weak force?
Solution
(a) The \(\displaystyle uud\) composition is the same as for a proton.
(b) \(\displaystyle 3.3×10^{−24}s\)
(c) Strong (short lifetime)
54. Accelerators such as the Triangle Universities Meson Facility (TRIUMF) in British Columbia produce secondary beams of pions by having an intense primary proton beam strike a target. Such “meson factories” have been used for many years to study the interaction of pions with nuclei and, hence, the strong nuclear force. One reaction that occurs is \(\displaystyle π^++p→Δ^{++}→π^++p\), where the \(\displaystyle Δ^{++}\) is a very short-lived particle. The graph in Figure shows the probability of this reaction as a function of energy. The width of the bump is the uncertainty in energy due to the short lifetime of the \(\displaystyle Δ^{++}\).
(a) Find this lifetime.
(b) Verify from the quark composition of the particles that this reaction annihilates and then re-creates a \(\displaystyle d\) quark and a \(\displaystyle \bar{d}\) antiquark by writing the reaction and decay in terms of quarks.
(c) Draw a Feynman diagram of the production and decay of the \(\displaystyle Δ^{++}\) showing the individual quarks involved.
This graph shows the probability of an interaction between a \(\displaystyle π^+\) and a proton as a function of energy. The bump is interpreted as a very short lived particle called a \(\displaystyle Δ^{++}\). The approximately 100-MeV width of the bump is due to the short lifetime of the \(\displaystyle Δ^{++}\).
55. The reaction \(\displaystyle π^++p→Δ^{++}\) (described in the preceding problem) takes place via the strong force.
(a) What is the baryon number of the \(\displaystyle Δ^{++}\) particle?
(b) Draw a Feynman diagram of the reaction showing the individual quarks involved.
Solution
a) \(\displaystyle Δ^{++}(uuu);B=\frac{1}{3}+\frac{1}{3}+\frac{1}{3}=1\)
b)
56. One of the decay modes of the omega minus is \(\displaystyle Ω^−→Ξ^0+π^−\).
(a) What is the change in strangeness?
(b) Verify that baryon number and charge are conserved, while lepton numbers are unaffected.
(c) Write the equation in terms of the constituent quarks, indicating that the weak force is responsible.
57. Repeat the previous problem for the decay mode \(\displaystyle Ω^−→Λ^0+K^−\).
Solution
(a) \(\displaystyle +1\)
(b) \(\displaystyle B=1=1+0, Z==0+(−1)\), all lepton numbers are 0 before and after
(c) \(\displaystyle (sss)→(uds)+(\bar{u}s)\)
58. One decay mode for the eta-zero meson is \(\displaystyle η^0→γ+γ\).
(a) Find the energy released.
(b) What is the uncertainty in the energy due to the short lifetime?
(c) Write the decay in terms of the constituent quarks.
(d) Verify that baryon number, lepton numbers, and charge are conserved.
59. One decay mode for the eta-zero meson is \(\displaystyle η^0→π^0+π^0\).
(a) Write the decay in terms of the quark constituents.
(b) How much energy is released?
(c) What is the ultimate release of energy, given the decay mode for the pi zero is π0→γ+γ?
Solution
(a) \(\displaystyle (u\bar{u}+d\bar{d})→(u\bar{u}+d\bar{d})+(u\bar{u}+d\bar{d})\)
(b) 277.9 MeV
(c) 547.9 MeV
60. Is the decay \(\displaystyle n→e^++e^−\) possible considering the appropriate conservation laws? State why or why not.
61. Is the decay \(\displaystyle μ^−→e^−+ν_e+ν_μ\) possible considering the appropriate conservation laws? State why or why not.
Solution
No. \(\displaystyle Charge=−1\) is conserved. \(\displaystyle L_{e_i}=0≠L_{e_f}=2\) is not conserved. \(\displaystyle L_μ=1\) is conserved.
62. (a) Is the decay \(\displaystyle Λ^0→n+π^0\) possible considering the appropriate conservation laws? State why or why not.
(b) Write the decay in terms of the quark constituents of the particles.
63. (a) Is the decay \(\displaystyle \sum{}^−→n+π^−\) possible considering the appropriate conservation laws? State why or why not. (b) Write the decay in terms of the quark constituents of the particles.
Solution
(a)Yes. \(\displaystyle Z=−1=0+(−1), B=1=1+0\), all lepton family numbers are 0 before and after, spontaneous since mass greater before reaction.
(b) \(\displaystyle dds→udd+\bar{u}d\)
64. The only combination of quark colors that produces a white baryon is RGB. Identify all the color combinations that can produce a white meson.
65. (a) Three quarks form a baryon. How many combinations of the six known quarks are there if all combinations are possible?
(b) This number is less than the number of known baryons. Explain why.
Solution
(a) 216
(b) There are more baryons observed because we have the 6 antiquarks and various mixtures of quarks (as for the π-meson) as well.
66. (a) Show that the conjectured decay of the proton, \(\displaystyle p→π^0+e^+\), violates conservation of baryon number and conservation of lepton number.
(b) What is the analogous decay process for the antiproton?
67. Verify the quantum numbers given for the \(\displaystyle Ω^+\) in [link] by adding the quantum numbers for its quark constituents as inferred from Table.
Solution
\(\displaystyle Ω+(\bar{s}\bar{s}\bar{s})\)
\(\displaystyle B=−\frac{1}{3}−\frac{1}{3}−\frac{1}{3}=−1,\)
\(\displaystyle L_e,μ,τ=0+0+0=0,\)
\(\displaystyle Q=\frac{1}{3}+\frac{1}{3}+\frac{1}{3}=1,\)
\(\displaystyle S=1+1+1=3.\)
68. Verify the quantum numbers given for the proton and neutron in [link] by adding the quantum numbers for their quark constituents as given in Table.
69. (a) How much energy would be released if the proton did decay via the conjectured reaction \(\displaystyle p→π^0+e^+\)?
(b) Given that the \(\displaystyle π^0\) decays to two \(\displaystyle γ\) s and that the \(\displaystyle e^+\) will find an electron to annihilate, what total energy is ultimately produced in proton decay?
(c) Why is this energy greater than the proton’s total mass (converted to energy)?
Solution
(a)803 MeV
(b) 938.8 MeV
(c) The annihilation energy of an extra electron is included in the total energy.
70. (a) Find the charge, baryon number, strangeness, charm, and bottomness of the \(\displaystyle J/Ψ\) particle from its quark composition.
(b) Do the same for the Υ particle.
71. There are particles called D -mesons. One of them is the \(\displaystyle D^+\) meson, which has a single positive charge and a baryon number of zero, also the value of its strangeness, topness, and bottomness. It has a charm of \(\displaystyle +1\). What is its quark configuration?
Solution
\(\displaystyle c\bar{d}\)
72. There are particles called bottom mesons or B -mesons. One of them is the \(\displaystyle B^−\) meson, which has a single negative charge; its baryon number is zero, as are its strangeness, charm, and topness. It has a bottomness of \(\displaystyle −1\). What is its quark configuration?
73. (a) What particle has the quark composition \(\displaystyle \bar{u}\bar{u}\bar{d}\)?
(b) What should its decay mode be?
Solution
a) The antiproton
b) \(\displaystyle p^−→π^0+e^−\)
74. (a) Show that all combinations of three quarks produce integral charges. Thus baryons must have integral charge.
(b) Show that all combinations of a quark and an antiquark produce only integral charges. Thus mesons must have integral charge.
33.6: Grand Unified Theories
75. Integrated Concepts
The intensity of cosmic ray radiation decreases rapidly with increasing energy, but there are occasionally extremely energetic cosmic rays that create a shower of radiation from all the particles they create by striking a nucleus in the atmosphere as seen in the figure given below. Suppose a cosmic ray particle having an energy of \(\displaystyle 10^{10}GeV\) converts its energy into particles with masses averaging \(\displaystyle 200MeV/c^2\).
(a) How many particles are created?
(b) If the particles rain down on a \(\displaystyle 1.00-km^2\) area, how many particles are there per square meter?
An extremely energetic cosmic ray creates a shower of particles on earth. The energy of these rare cosmic rays can approach a joule (about \(\displaystyle 10^{10}GeV\)) and, after multiple collisions, huge numbers of particles are created from this energy. Cosmic ray showers have been observed to extend over many square kilometers.
Solution
(a) \(\displaystyle 5×10^{10}\)
(b) \(\displaystyle 5×10^4particles/m^2\)
76. Integrated Concepts
Assuming conservation of momentum, what is the energy of each γ ray produced in the decay of a neutral at rest pion, in the reaction \(\displaystyle π^0→γ+γ\)?
77. Integrated Concepts
What is the wavelength of a 50-GeV electron, which is produced at SLAC? This provides an idea of the limit to the detail it can probe.
Solution
\(\displaystyle 2.5×10^{−17}m\)
78. Integrated Concepts
(a) Calculate the relativistic quantity \(\displaystyle γ=\frac{1}{\sqrt{1−v^2/c^2}}\) for 1.00-TeV protons produced at Fermilab.
(b) If such a proton created a \(\displaystyle π^+\) having the same speed, how long would its life be in the laboratory?
(c) How far could it travel in this time?
79. Integrated Concepts
The primary decay mode for the negative pion is \(\displaystyle π^−→μ^−+\bar{ν_μ}\).
(a) What is the energy release in MeV in this decay?
(b) Using conservation of momentum, how much energy does each of the decay products receive, given the \(\displaystyle π^−\) is at rest when it decays? You may assume the muon antineutrino is massless and has momentum \(\displaystyle p=E/c\), just like a photon.
Solution
(a) 33.9 MeV
(b) Muon antineutrino 29.8 MeV, muon 4.1 MeV (kinetic energy)
80. Integrated Concepts
Plans for an accelerator that produces a secondary beam of K-mesons to scatter from nuclei, for the purpose of studying the strong force, call for them to have a kinetic energy of 500 MeV.
(a) What would the relativistic quantity \(\displaystyle γ=\frac{1}{\sqrt{1−v^2/c^2}}\) be for these particles?
(b) How long would their average lifetime be in the laboratory?
(c) How far could they travel in this time?
81. Integrated Concepts
Suppose you are designing a proton decay experiment and you can detect 50 percent of the proton decays in a tank of water.
(a) How many kilograms of water would you need to see one decay per month, assuming a lifetime of \(\displaystyle 10^{31}y\)?
(b) How many cubic meters of water is this?
(c) If the actual lifetime is \(\displaystyle 10^{33}y\), how long would you have to wait on an average to see a single proton decay?
Solution
(a) \(\displaystyle 7.2×10^5kg\)
(b) \(\displaystyle 7.2×10^2m^3\)
(c) 100 months
82. Integrated Concepts
In supernovas, neutrinos are produced in huge amounts. They were detected from the 1987A supernova in the Magellanic Cloud, which is about 120,000 light years away from the Earth (relatively close to our Milky Way galaxy). If neutrinos have a mass, they cannot travel at the speed of light, but if their mass is small, they can get close.
(a) Suppose a neutrino with a \(\displaystyle 7-eV/c^2\) mass has a kinetic energy of 700 keV. Find the relativistic quantity \(\displaystyle γ=\frac{1}{\sqrt{1−v^2/c^2}}\) for it.
(b) If the neutrino leaves the 1987A supernova at the same time as a photon and both travel to Earth, how much sooner does the photon arrive? This is not a large time difference, given that it is impossible to know which neutrino left with which photon and the poor efficiency of the neutrino detectors. Thus, the fact that neutrinos were observed within hours of the brightening of the supernova only places an upper limit on the neutrino’s mass. (Hint: You may need to use a series expansion to find v for the neutrino, since its γ is so large.)
83. Construct Your Own Problem
Consider an ultrahigh-energy cosmic ray entering the Earth’s atmosphere (some have energies approaching a joule). Construct a problem in which you calculate the energy of the particle based on the number of particles in an observed cosmic ray shower. Among the things to consider are the average mass of the shower particles, the average number per square meter, and the extent (number of square meters covered) of the shower. Express the energy in eV and joules.
84. Construct Your Own Problem
Consider a detector needed to observe the proposed, but extremely rare, decay of an electron. Construct a problem in which you calculate the amount of matter needed in the detector to be able to observe the decay, assuming that it has a signature that is clearly identifiable. Among the things to consider are the estimated half life (long for rare events), and the number of decays per unit time that you wish to observe, as well as the number of electrons in the detector substance.
Contributors and Attributions
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Paul Peter Urone (Professor Emeritus at California State University, Sacramento) and Roger Hinrichs (State University of New York, College at Oswego) with Contributing Authors: Kim Dirks (University of Auckland) and Manjula Sharma (University of Sydney). This work is licensed by OpenStax University Physics under a Creative Commons Attribution License (by 4.0) .


6.1: Credit
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Introduction: Financial Health
Much like our physical and mental health, our financial health is extremely important. When we talk about our overall health, we often neglect the topic of our finances. Financial stress not only affects our mental and physical well-being but also can affect our ability to finish school or gain employment. This chapter will introduce you to tips and strategies to assist you in maintaining your financial health and well-being.
This chapter focuses on personal finances, but as a college student, financial aid and paying for college are important elements of your financial health. Please see the “College Resources and Policies” chapter for information about how to apply for financial aid including student loans, grants and scholarships.
We would like to thank the Pennsylvania State Employees Credit Union (PSECU) for providing most of the content in this chapter. PSECU is a credit union with locations around Pennsylvania, including some locations on HACC campuses. To learn more about PSECU, please visit their website at psecu.com.
Money Management Essentials
Content provided by PSECU , Pennsylvania State Employees Credit Union.
A lot of things compete for college students’ attention. Finishing assignments, passing exams, looking for jobs or internships, managing family obligations - the list goes on and on. While these tasks are all important things on which to focus, learning how to manage your personal finances is crucial as well.
Personal finance is a broad subject made up of many components. We’ll zero in on a few key areas – credit, choosing loans and managing debt responsibly and budgeting. Understanding these money management essentials can help you build a strong financial foundation to support your success now and in the future.
6.1 Credit
Many potential lenders, employers, and landlords, among others, will check your credit to determine if you’re a qualified borrower, employee, or tenant. If you don’t know much about credit, you may just cross your fingers and hope for the best when someone asks to check your credit. With so many important things riding on credit, however, students should get informed now.
What is Credit?
Everyone talks about “credit,” but it’s rare to hear someone explain what it actually is . Simply put, credit is your ability to borrow money or to buy something without paying in full upfront.
You may need to utilize credit when making large purchases, like a home or car, which many people don’t have the cash to buy outright. Even if you’re not planning a large purchase, credit will play a vital role in smaller tasks, like applying for a credit card, getting approved for a cell phone plan, or turning on utilities in a new apartment. The better your credit, the more likely lenders or providers are to believe that you’ll pay off your debt in the future and the easier these tasks, among many others, may be for you.
How Does Someone Check Your Credit?
Now that you know what credit is, you may be wondering how someone can check it. Typically, when someone says they are going to check your credit they are referring to your credit score and/or your credit report.
Credit Scores
Your credit score is a three-digit number that allows whoever is checking to compare you against other potential borrowers. There are many different scoring models, and what is a “good” score can vary between each one. In general, though, a higher score reflects better credit.
A credit score has five different components. Each component makes up a percentage of the score, as indicated below:
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Payment History (35%) – Paying bills on time is the best way to build and maintain good credit. More than a third of your credit score is based on this simple habit. Missing a payment can impact your credit score negatively for up to seven years, so keeping track of when your payments are due is important.
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Amount Owed (30%) – How much you owe accounts for almost a third of your credit score. Even if you always pay your bills on time, carrying high balances on credit cards or large amounts of debt can hurt your score.
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Length of Credit History (15%) – This part of the credit score reflects how long you’ve had established credit and the average ages of your accounts. Typically, the longer you’ve had established credit, the higher this portion of your credit score will be.
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Credit Mix (10%) – There’s a difference between revolving credit and installment loans. Revolving credit is credit that is available to you on an ongoing basis. When you spend a portion of the credit, that credit is unavailable until you pay it back. Once that credit is paid back, the credit is available for you to use again. A good example of revolving credit is a credit card. Installment loans, on the other hand, are debts that are paid off in set monthly payments. The money doesn’t become available again after you repay but simply reduces the amount you owe. The most common examples of installment loans are student loans or car loans. Installment loans typically are seen in a more positive light than revolving credit. The mix of credit types you use impacts this portion of your score.
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New Credit (10%) – Each new credit account you open impacts your credit score. Therefore, you should avoid opening multiple accounts over a short period of time. The exact impact may depend on the type, dollar amount, and number of new accounts, but overall, borrowers who have opened several new accounts in a short period are riskier to lenders.
Credit Reports
Your credit score is calculated from information in your credit report . In the same way that your school transcript is a record of your academic history, your credit report is a record of your financial history. It gives those who are checking your credit a more in-depth look at what’s behind your credit score.
Your credit report contains four main sections:
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Personal Information - This section includes identifying information that links the report to you, such as your name, birthdate, Social Security number, and address.
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Account Information/Trade Lines - This portion shows what credit accounts you have open, the total amount of each loan or credit limit, what payments you make, and whether or not you make your payments on time. It may also show closed accounts. Closed accounts typically remain on your report for up to ten years if those accounts were in good standing when closed and seven years if the accounts were charged off or in bad standing.
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Public Records - If there are verifiable financial judgments, bankruptcies, or tax liens in your name, those records will be displayed in this section.
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Inquiries - If you’ve applied for credit or anyone has checked your credit in the past two years, those inquiries will be listed here. There are two types of inquiries listed in this section:
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A hard pull generally means a lender is looking at the report to make a lending decision, such as when you apply for an auto loan or to open a new credit card. These inquiries sometimes are labeled as “viewable to everyone,” which means anyone checking your credit report can see these inquiries.
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A soft pull is not done to make a lending decision, but for another purpose, such as monitoring your own credit. Soft pulls have no effect on your credit score and sometimes are labeled as “viewable only by you,” because these inquiries won’t display on your report when others check.
Can I Check My Own Credit?
Now that you’re aware of all the people who may inquire about your credit, you may be wondering “Can I check my own credit?”
The answer is yes. You can and should check your credit on a regular basis. Keeping tabs on your credit not only helps you understand your financial standing, but also can aid you in identifying and stopping fraudulent activity that could be occurring in your name.
How to Access Your Credit Report
You’re entitled to a free copy of your credit report from each of the three major credit reporting agencies once a year. You can access these free reports by visiting AnnualCreditReport.com’s website .
When you’re checking your credit report, make sure you’re typing in the correct URL. You’ll have to enter personal information, such as your name, date of birth, and Social Security number, in order to access your report, so you want to make sure you land at the correct site. You shouldn’t be prompted to provide any financial account or credit card information if you’re in the right place.
In a typical year, you’ll be able to see your report for free from each agency once a year, meaning once every 12 months, not once a calendar year. You can choose to check your reports from all agencies at once or space out your inquiries so that you can see a different report every few months. Some people prefer to see them all at once so they can do a thorough review of all reports at the same time. Others prefer to space out the reports, so they have a more frequent pulse on their credit. There’s no wrong or right approach - it's simply a matter of personal preference.
Once you pull your report, you’ll want to review the report for accuracy. To help you through this process, view the Credit Report Review Checklist and information about reporting errors in this chapter.
How to Access Your Credit Score
When you’re reviewing your credit report, you’ll notice that your credit score isn’t included. Unlike your credit report, there are no regulations granting you free access to your credit score. In many cases, you must pay to see your score. However, some financial institutions provide members or customers with monthly or quarterly access to their credit scores by meeting certain criteria such as opening a checking account or taking out a loan.
Credit Report Review Checklist
You can request your credit report for free once a year from three major credit reporting companies at www.AnnualCreditReport.com . Once you’ve downloaded your credit report, use this checklist as a guide to review each section.
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All my personal information is correct, including:
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Name
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Social Security number
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Current and previous address(es)
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Current phone number
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Marital status
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Employment history
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Any additional personal information listed
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All items listed in the Public Records section, if any, are correct.
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All accounts listed in the Accounts Open/Trade Lines section are accounts I opened.
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All information in the Accounts Open/Trade Lines section is correct, including:
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Account numbers
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Status of all accounts (open vs. closed)
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Ownership of accounts (i.e. individual, joint, or authorized user)
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Payment history (i.e. current, 30 days delinquent)
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Current balances (including debts paid in full)
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All hard inquiries (sometimes listed as “viewable by others”) are correct.
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I have saved my credit report in a secure digital or physical location.
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I have noted and reported any errors found on my credit report, using the instructions in italics below.
If you find errors or believe an account was opened fraudulently in your name, visit Link Annual Credit Report Dispute [www.annualcreditreport.com] for information on filing disputes with the credit reporting agency that issued the report and the business that provided the information.
How Can I Build or Repair Credit?
The more you realize the importance of credit, the more concerned you may become with building and maintaining good credit. Here are some tips to help you get started whether you’re establishing credit for the first time or repairing your credit after getting off track.
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Pay all bills on time – As previously noted, payment history makes up more than a third of your credit score. So, making payments on time not only helps you avoid late fees, but keeps you from negatively impacting your credit as well. If you need help remembering when your payments are due, consider setting up reminders on your phone or calendar.
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Don’t open several new accounts at once – Consider credit and loan offers carefully. Make sure a credit card is one you’ll use with a good interest rate and no or low fees.
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Use credit cards responsibly – Only make purchases you can pay off in full to avoid carrying a balance and accruing interest. Before you open a credit card, understand the interest rate and be aware of any associated fees or penalties.
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Make paying down a debt a priority – Make more than the minimum payment on credit cards and loans whenever you’re able. Avoid accruing new credit card debt and talk with your creditors about how to bring your accounts into good standing if you’ve made late payments in the past.
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Monitor your credit – Keeping tabs on your credit can help you identify any incorrect information or fraudulent activity immediately. Getting these items off your report may help increase your score.


13: Adolescence - Physical Development
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learning objectives
After this chapter, you should be able to:
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Explain the changes in physical growth and brain growth
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Compare and contrast different male and female changes that occur during puberty
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Discuss teenage pregnancy, birth control, and sexual health
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Summarize adolescent health: sleep, diet, and exercise
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Discuss drug and substance abuse
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Explain the prevalence, risk factors, and consequences of adolescent pregnancy and sexual health
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Describe several mental health issues for teens
Adolescence is often defined as the period that begins with puberty and ends with the transition to adulthood. The commonly accepted beginning age for this period of development is age 12. When adolescence ends is harder to pin down. When does adulthood truly begin? Are we an adult at 18 years of age? Or 20? Or even older? Adolescence physical development has evolved historically, with evidence indicating that this stage is lengthening as individuals start puberty earlier and transition to adulthood later than in the past. Puberty today begins, on average, at age 10–11 years for girls and 11–12 years for boys. This average age of onset has decreased gradually over time since the 19th century by 3–4 months per decade, which has been attributed to a range of factors including better nutrition, obesity, increased father absence, and other environmental factors (Steinberg, 2013). Completion of formal education, financial independence from parents, marriage, and parenthood have all been markers of the end of adolescence and beginning of adulthood, and all of these transitions happen, on average, later now than in the past.
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13.1: Physical Growth
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The adolescent growth spurt is a rapid increase in an individual’s height and weight during puberty resulting from the simultaneous release of growth hormones, thyroid hormones, and androgens. Males experience their growth spurt about two years later than females. The accelerated growth in various body parts happens at different times, but for all adolescents it has a fairly regular sequence: the extremities grow first, followed by the arms and legs, and later the torso and shoulders.
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13.2: Brain Growth
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Brain Growth continues into the early 20s. The development of the frontal lobe, in particular, is important during this stage. Adolescents often engage in increased risk-taking behaviors and experience heightened emotions during puberty; this may be due to the fact that the frontal lobes of their brains—which are responsible for judgment, impulse control, and planning—are still maturing until early adulthood.
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13.3: Physical Changes in Adolescence
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Adolescence begins with the onset of puberty, a developmental period in which hormonal changes cause rapid physical alterations in the body, culminating in sexual maturity. Although the timing varies to some degree across cultures, the average age range for reaching puberty is between 9 and 14 years for girls and between 10 and 17 years for boys (Marshall & Tanner, 1986). This period of physical development of the adolescent age 9-13 is divided into two phases.
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13.4: Adolescent Health- Sleep, Diet, and Exercise
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According to the National Sleep Foundation (NSF) (2016), adolescents need about 8 to 10 hours of sleep each night to function best. The most recent Sleep in America poll in 2006 indicated that adolescents between sixth and twelfth grade were not getting the recommended amount of sleep.
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13.5: Maintaining Emotional Health
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Emotional regulation is the ability to successfully control our emotions, which takes effort, but the ability to do so can have important positive health outcomes. Emotional responses such as the stress reaction are useful in warning us about potential danger and in mobilizing our response to it, so it is a good thing that we have them.
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13.6: Disorders and Syndromes
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A psychological disorder is an unusual, distressing, and dysfunctional pattern of thought, emotion, or behavior. Psychological disorders are often co-occurring or comorbid, meaning that a given person suffers from more than one disorder. Psychologists diagnose a disorder using the Diagnostic and Statistical Manual of Mental Disorders (DSM).
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13.S: Summary
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Thumbnail: www.pexels.com/photo/woman-putting-on-makeup-3059392/


8.1.3: Special Funding Strategies
Learning Objectives
By the end of this section, you will be able to:
- Identify funding strategies used by charitable organizations
- Describe financing opportunities available to startups
- Define bootstrapping
- Describe the advantages and disadvantages of bootstrapping
It’s important to recognize that not all startups are Silicon Valley tech companies. These companies create high-profile products, such as applications and websites, which can take years to become profitable or even generate revenue. Much more common are the small businesses founded every day by entrepreneurs seeking to create value in their local communities. Moreover, not all startups are founded with a profit motive in mind.
Charitable organizations , or certain nonprofit companies, are often founded for altruistic purposes, such as advancing the arts, education, and science; protecting the natural environment; providing disaster relief; and defending human rights.
| Mission | Examples |
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| Advance education | Teach for America, Khan Academy |
| Protect the natural environment | Sierra Club, Wildlife Conservation Society |
| Defend human rights | Amnesty International, Human Rights Watch |
| Provide disaster relief | American Red Cross |
| Support the arts | Metropolitan Museum of Art, Americans for the Arts |
These goals supersede the profit motive that a traditional company would have. As a result, the funding strategies of these enterprises often differ quite dramatically from those of standard for-profit businesses. Without the emphasis on profit, it can be difficult to provide for the cost of ongoing operations. Thus, these organizations must develop a sustainable strategy —one that can maintain the organization’s financial stability.
In the United States, such organizations can qualify for tax-exempt status , meaning that if there is a profit from operations, it is not typically subject to taxes. Organizations seeking this exemption must apply to the Internal Revenue Service for tax-exempt status and provide information about what kind of mission the organization carries out—charitable, scientific, educational, and so on.
Consider a museum. What is its purpose? Traditional companies provide a product or service to their customers in exchange for payment, and typically fill a need their customers have. A grocery store sells food because human beings need to eat food to survive. Although viewing paintings and sculptures is not a physical requirement for life, this experience arguably enriches our lives and helps educate and shape our society. That is why museums are founded. Consider the original mission statement of the Metropolitan Museum of Art (commonly known as the “Met”) in New York City.
This is a different goal than that of most small businesses (providing a product or service in exchange for a profit) and, as a result, requires different financing strategies, such as a combination of program services, donations, and grants.
LINK TO LEARNING
Go to the Internal Revenue Service’s website and look at the most recently updated Pub 334 Tax Guide for Small Business to learn more about the rules for income tax preparation for a small business.
Program Services
Program services are the basic offerings that a nonprofit organization provides that result in revenue, although not typically enough to cover the overall cost of running the organization. These services most closely resemble the customer interactions of a traditional business. The organization provides a product or service in exchange for a customer’s money.
In our museum example, program services could take a few different forms. First, the museum likely charges a fee for admission to view the artwork and artifacts. The individual ticket price multiplied by the number of museum visitors equals the museum’s ticket revenue. An established museum will have a good sense of how many visitors it has on average and can use these data to create a budget.
Another source of program service revenue for a museum could take the form of hands-on educational activities or events with guest speakers or presenters. Often museums will host local artists, or their own employees might conduct art classes or special-topic tours. These events and activities typically have a charge (revenue) beyond the regular admission cost.
Despite these revenue-generating activities, nonprofit organizations still face many funding challenges in covering all the operating costs of a normal business, such as employee wages, facility costs, and advertising. Thus, they need many different sources of income. To illustrate, the Met’s 2018 program service income only made up 2.3 percent of its total revenue for the year.
Donations
One benefit to a business with a charitable mission is inherent public support, which can foster community involvement above and beyond patronage. For nonprofits, this can translate into a willingness to donate money to the organization. A donation is a financial gift with no expectation of repayment or receiving anything in return. A traditional business must provide something valuable to create a customer exchange: Their customers demand value in exchange for their hard-earned money.
The benefactors of a charitable organization want to help further the mission of the organization. This type of entity—whether it’s a museum, a hospital, or the Red Cross—relies on the goodwill of community supporters. For the Met, with such a low percentage of revenue generated by program services, it’s clear that donations and charitable gifts are vital to the organization’s financial viability .
Grants
Another source of funding for nonprofit organizations is grants. A grant is a financial gift given for a specific purpose by a government agency or a charitable organization such as the Bill and Melinda Gates Foundation. Like a donation, a grant does not have to be repaid. Unlike with donations, both nonprofit and for-profit organizations can compete for grants. Whereas donations are typically given without restriction to offset the general operating expenses of the organization, grants often specify how the funds are to be used. Most grant-providing entities have an agenda or purpose behind their funding. For example, the National Institutes of Health (NIH) provides grants “to support the advancement of the NIH mission to enhance health, extend healthy lives, and reduce the burdens of illness and disability.” This federal organization invests over $32 billion annually for medical research.
Grants can be very competitive, requiring a rigorous application process. Usually, multiple organizations apply for the same grant; the organization issuing the grant reviews the many competing applications to make its selection. Grantees generally must submit audited financial statements and are required to update the grantor subsequent to the grant award to ensure proper intended use. The NIH awards almost 50,000 grants annually, most of which are competitive. Although that is an enormous number of projects to fund, only 20 percent of applications submitted to the NIH in 2018 actually were accepted. In other words, the NIH rejected four out of every five applications. For entrepreneurs, this means that when you identify a grant that is specific to your organization’s mission, you should weigh your chances of being awarded the grant when considering it as part of your funding strategy.
To understand grants in practice, let’s further examine the NIH. The NIH Small Grant Program provides funds for activities such as the development of new research technology. This specific grant can be awarded for up to a two-year period, with funds of up to $50,000 in direct costs per year. A grant like this could provide vital support to a nonprofit startup.
Some business ventures fall somewhere between organizations completely committed to charitable work and traditional small businesses with entrepreneurs focused on social entrepreneurship. Social entrepreneurs develop products and services as solutions to societal problems. For example, the TOMS shoe company was able to create a business model through which the company gives one pair of shoes to children in need in foreign countries for every pair of shoes that a customer purchases. This practice pioneered what they refer to as “One for One.”
The company’s website describes the origins of both the company and this model, which are based on the experiences of its founder, Blake Mycoskie.
Social entrepreneurship offers the ability to effect positive change in the world without simply relying on donations. It pairs a profitable, sustainable business model with a good cause. This combination often creates positive word of mouth. It gives potential customers a good feeling about the product beyond just its style or function.

Social Entrepreneurship
Like the founder of TOMS, sometimes in our everyday life, we are presented with an opportunity to help people. We may even find out that we’re not alone in this desire to help. What opportunities to help—individuals, society, or environment—do you see in your own community? What are some ways that you could raise awareness around this issue?
No-Loan Finance Strategies
As you’ve learned, many startups come into being through the extensive use of debt. Although borrowing is a legitimate source of funding, it can be risky, especially if the entrepreneur is personally responsible for repayment. In practice, some entrepreneurs max out credit cards, take out home-equity loans against their primary residences, or secure other high-interest personal loans. If the entrepreneur fails to repay the loans, the result can be repossession of equipment, home foreclosure, and other legal action.
We now examine funding strategies attractive to many startups that do not require going into debt or exchanging ownership of the business for financial support (debt and equity financing). The financing methods described here are more creative funding strategies, including crowdfunding, bartering, and other methods.
Crowdfunding
Recall the story of iBackPack. This venture was originally funded by contributions through Indiegogo and Kickstarter. These websites are a form of crowdfunding , which involves collecting small sums of money from a large number of people. The people who contribute money are typically referred to as backers because they are backing the project or supporting the business idea.
Browsing these crowdfunding websites, you will see many different kinds of ventures seeking financial backing—from creating new board games to opening donut cafes. Each project identifies an overall specific funding goal in terms of a dollar amount. Some crowdfunding websites, such as Kickstarter, implement an “all or nothing” model in which projects do not receive any funds unless their overall funding goal is met. The amount can be exceeded, but if it is not met, the project receives nothing. For an entrepreneur utilizing this resource, selecting an attainable funding goal must be a core part of their strategy. The funding goal must also be appropriate to the scale of the project. For example, setting a goal of $50,000 may be reasonable for launching a food truck (which could be a prototype for a full restaurant), but it is a mere fraction of the cost of constructing an entire table-service restaurant, which would come closer to $750,000. An entrepreneur seeking to enter the culinary world should consider which target would be most achievable as well as most beneficial in meeting both short- and long-term goals. Also, remember that meeting the funding goal does not ensure success of the business, as was the case with iBackPack.
Entrepreneurs vying for crowdfunding usually employ some common tactics. First, they often post an introductory video that explains the project goal and the specific value proposition. (For example, a chef might seek $75,000 to open a food truck specializing in a relatively unknown cuisine.) Second, the entrepreneur provides a more detailed written summary of the project, often including specific items that the funding will pay for, such as $50,000 for a vehicle, $10,000 for graphic design and vehicle decals, and $15,000 for kitchen equipment for the truck. Last is the reward structure, which is what entices visitors to the site to fund the project, offering a return beyond their own passion for the venture. The reward structure establishes different levels of funding and ties a specific reward to each level. For example, for a contribution of $5, the chef might thank the backer on social media; for $25, the backer would get a t-shirt and a hat featuring the food truck’s logo; for $100, the backer would get five free meals when the food truck opens. Fees for these crowdfunding sites vary from 5 to 8 percent. Kickstarter now requires physical products or prototypes for some startups, as well as a short video to help represent and “sell” the product.
Although this financing source offers a lot of flexibility, businesses utilizing crowdfunding can run into trouble. Certain funding levels and rewards may have limits. For example, a reward structure might offer backers contributing $1,000 a trip to the grand opening of the food truck, including airfare and hotel. These top-tier rewards can generate a lot of excitement, but the expense of flying people around the country and providing accommodations could become unmanageable. One research study stated that 84 percent of Kickstarter’s top projects delivered their rewards late.
The advantage of crowdfunding is that the business receives cash upfront to launch. The downside is that the reward requires a future payment to the backers. This payment may be in the form of branded merchandise, meals, or even events or travel, so it is important for entrepreneurs to set aside part of the investment money to fund the rewards. Depending solely on generating the reward funds out of future sales is a risk that might result in upsetting the very fans who made the business possible. Since crowdfunding is managed online, another risk is upsetting the project’s vocal supporters. Crowdfunding usually provides only a “kick start” for a startup, so most seed-stage companies will need additional funding from other sources to get to their first commercial launch.
Although social media can backfire, entrepreneurs can take advantage of benefits too. Crowdfunding can allow an entrepreneur to build a community around a product before it is even sold. Like-minded fans of a product can connect with each other over the internet, in the feedback section of a website, or in shared social media posts. Additionally, backers of a project can become cheerleaders for it by sharing the idea—and their enthusiasm for it—with friends, family, and coworkers. Word-of-mouth marketing can lead to more backers or future customers after launch.
Dozens of crowdfunding portals exist, including WeFunder, SeedInvest, Kickstarter, and Crowdcube. Current SEC guidelines for issuing and investing limits granted for Title III Crowdfunding include:
- A company can raise up to $1 million in aggregate through crowdfunding offerings over a twelve-month period
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Over a twelve-month period, individual investors can invest in the aggregate across all crowdfunding offerings up to:
- $2,000 or 5 percent of the unaccredited investors net worth or yearly income if they make less than $100,000/year
- 10 percent of the lesser of their annual income or net worth, if both their annual income and net worth are equal to or more than $100,000
ARE YOU READY?
Kickstarter
Visit the Kickstarter website at https://www.kickstarter.com/ and review a few projects. What did they do well in the video pitch? What unique rewards did they offer? How would you implement a Kickstarter page for your own business idea?
Bartering
Startup companies often don’t have a lot of cash assets on hand to spend, but they often have offerings that can provide value to other businesses. Bartering is a system of exchanging goods or services for other goods or services instead of for money. Let’s consider the case of Shanti, a website designer who wants to start a business. She may want to have her business formally incorporated or may require other legal help, such as review of standard contracts. Hiring a lawyer outright for these services can be costly, but what if the lawyer needed something that a website designer could provide?
Whether the lawyer has just started his own business or has been established for several years, he may need a website created or have an old website redesigned and updated. This website overhaul could prove costly for the lawyer. But what if there were a way that both the lawyer and the web designer could get what they wanted with a resulting net cost of zero dollars? Bartering can achieve this. It should be noted that there are accounting and tax implications involved with bartering that can prevent a net zero offset of costs.
In a barter scenario, Shanti could create a website for the lawyer at the expense only of her time, which in the startup phase is often more abundant than actual cash. The lawyer could provide incorporation services or contract review in exchange, requiring no cash outlay. For many entrepreneurs, this type of exchange is appealing and enables them to meet business needs at a lower perceived cost. Although more mature firms can also use bartering, the opportunity cost is much higher. If a mature company is unable to take on a new paying client because it is doing too much free (barter) work, it may lose out on future revenue, which could potentially be a big loss. Startups, in contrast, often have excess capacity while they develop a customer base, so taking on barter work is often a low-risk, beneficial funding strategy.
Other No-Loan Funding Options
Beyond crowdfunding and bartering, startups have other options to help them get off the ground, such as funding competitions and pre-orders. Many organizations hold entrepreneurial finance contests provide financial awards to the winners. These prize funds can be used as seed money to start a new venture. For example, the New York City Public Library holds an annual business plan competition called the New York StartUP! Business Plan Competition. Applicants must complete an orientation session, attend workshops that develop skills related to the creation of a business plan, and submit a complete business plan. The first-place award yields $15,000 in prize money, which can be a great start toward turning an entrepreneurial idea into a business reality.
Another way for startups to gain financial traction is to solicit pre-orders. Consider the launch of a new book or video game. Retail stores will often solicit pre-orders, which are advance purchases of the product. Customers pay for the desired item before they even have access. For example, the entrepreneur Mitchell Harper raised $248,000 in funds before his product launched. This approach is not limited to existing, well-known franchises—startups can use it as well. Although established novel and video game franchises have big fan bases and often large advertising budgets, startups can still find effective strategies in this space.
Companies with a prototype model of their product or a first manufacturing run can showcase the new product to potential customers, who may be interested enough to place an order. The company can use the funds received from these pre-orders to pay for the inventory. In addition to having sales staff make sales calls, new companies can attend trade shows and exhibitions to garner interest in the product. Many new products are launched in this fashion because it allows access to many potential customers in one place.
Why Bootstrapping Hurts, Then Helps
The process of self-funding a company is typically referred to as bootstrapping , based on the old adage that urges us to “pull ourselves up by our bootstraps.” It describes a funding strategy that seeks to optimize use of personal funds and other creative strategies (such as bartering) to minimize cash outflows. In recent years, this strategy has been the fodder for shows like Shark Tank . These shows may make entrepreneurs think that being on TV is glamorous, or the shows may glorify the financial backing of millionaires and billionaires. We have seen that for many entrepreneurs, the reality is that there are drawbacks to bringing in outside investors to launch your venture. These drawbacks include loss of future profits and possible loss of control of the company, among others. Potential business owners must weigh the advantages and disadvantages—both short and long term—for funding their specific dream.
You’ve learned about financing strategies predicated on finding a willing investor or lender, but many small businesses simply don’t have access to large amounts, or any amount, of capital. In these cases, aspiring business owners need lean business strategies that will yield the greatest benefit.
Bootstrapping requires entrepreneurs to shed any preconceived notions of the popular-culture image of startups. Most startups don’t have trendy downtown offices, foosball tables, or personal chefs. Bootstrapping reality looks more like late nights spent clipping coupons. It involves scrutinizing potential expenses and whether each cost is really worth the investment. It can be a difficult and trying process, but without any angel investors or wealthy family backers, bootstrapping is often an entrepreneur’s only option. The good news is that this approach can pay substantial dividends in the long run.
The Basics of Bootstrapping
When entrepreneurs risk their life savings, they must stretch every dollar as far as possible. Having a limited amount of capital to work with requires optimizing creative strategies to get the business launched and keep it afloat. This creativity applies to bringing customers and sales in the door as well as to managing expenses.
Understanding the ongoing costs of the business is key. In an interview on NPR’s show How I Built This , Barbara Corcoran, one of the investors on Shark Tank , shares her humble beginnings in real estate brokerage. One of the things she touches on is being constantly aware of how long her money would last, given her monthly expenses. If she had $10,000 in the bank and the cost of her rent and employees was $2,500 per month, she knew that the money would last her four months. Such constant information and vigilance are required when bootstrapping a business for success.
Employee costs are typically one of the largest expenses facing a business. Hiring traditional full-time employees can be costly; onboarding them too early can be fatal to a business’s bottom line. Creative approaches to minimizing labor costs can be enormously helpful. One strategy for controlling these costs is utilizing independent contractors (freelancers) and other part-time employees. They do not work full-time for the business and may serve other companies as well. Their compensation is generally lower than that of a full-time, salaried employee, often in part because these positions do not usually come with any benefits, such as health insurance or paid time off. Using these workers to fill resource needs can help minimize costs. Once operations have begun to stabilize, it may be possible and ideal to offer full-time employment to these individuals.
Marketing is another key area for new business investment, but billboards, web ads, TV ads, and radio spots can be expensive. TV and radio ads can also be ineffective if they are aired during low-volume times, which is typically all that startups with lower budgets can afford. Fortunately, there are many low- or no-cost marking opportunities, such as word-of-mouth marketing. Doing a good job for one customer can easily lead to referrals for more business. Some social media efforts can also provide a strong return for minimal investment, although typically it is nearly impossible to gauge an effort’s potential impact or success.
A new enterprise that is bootstrapping must also carefully manage operational expenses. At the beginning of operations, an entrepreneur can often minimize unnecessary expenses—even if that means forgoing an actual business location. Working out of a home office or a co-working space (such as WeWork or Impact Hub) can lead to significant savings. Renting office space can cost hundreds or thousands of dollars a month, whereas a home office typically requires no additional investment. Depending on the location, co-working spaces can provide a single workspace and technology access for as little as $50 to $100 per month, yielding substantial savings over a dedicated office suite. In larger cities, or in locations with more amenities, the monthly costs can run between $100 and $500 per month.
The Boston Beer Company, which today produces the Samuel Adams line of beers, provides a classic example of minimizing these costs in its early days. When this company first started, it owned no office space—or even a brewery. It employed other breweries as contract brewers to manufacture its beer. Its founder, Jim Koch, invested most of his time in selling to bars and restaurants, working from his car and phone booths. (This was during the 1980s.) His lean strategy was a successful application of the bootstrapping mindset. From its humble beginnings, the Boston Beer Company has become one of the largest American-owned breweries—ranked second based on 2018 sales volume by the Brewers Association. Whereas traditional thinking may dictate that a company must have an official office or headquarters, a bootstrapping mindset evaluates what the space would be used for and the trade-offs for its cost.
How Bootstrapping Hurts
The process of bootstrapping is not an easy one. It is fraught with tight budgeting and sacrifice, which can take its toll on an entrepreneur. One of the simplest bootstrapping strategies is to start a business by moonlighting , or treating your business venture as a second job. Employing this strategy, the entrepreneur continues to work at their regular job, say from 9:00–5:00, and then dedicates the rest of the evening and weekends to working on the business. Whereas this strategy has the obvious benefit of maintaining a comfortable level of income, this approach has a few drawbacks (Table 9.3). Moonlighting entrepreneurs cannot dedicate 100 percent of their time and energy to their new business. The time they can dedicate to it may be less efficient. After working all day at another job, a person may feel tired or burned out, so it can be difficult to change gears and press forward with full productivity.
In addition to the exhausting time investment, moonlighting can exact tolls on personal relationships. This strategy is easiest when an entrepreneur is in a life stage with few commitments. It may have an adverse effect on friendships, but in other life stages, this impact can be more significant. For example, it can detract from relationships with a partner/spouse or children, in both a decrease in focus/investment in these relationships and day-to-day challenges in work-life balance and household management for all affected. Additionally, at some point, to attract serious investors, a founder will have to commit to the project full time.
| Advantages | Disadvantages |
|---|---|
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Other bootstrapping strategies include negotiating the terms for payments on expenses. Often when businesses sell to other businesses, the vendor allows the customer to buy on credit . This means that the buyer does not have to pay at the time of purchase. Although retail customers are required to pay at the register during checkout, purchases between businesses can work on different terms, sometimes extended up to thirty, sixty, or ninety days. This extra time to pay for purchases can be a real advantage for businesses. When a business buys inventory on credit, it has the opportunity to begin selling it before it has even paid for it. For example, a clothing retailer could sell its product in stores or online, and receive cash before it had to pay its vendors. Unfortunately, when a business’s cash becomes tight, an ethical dilemma can arise. When a business has more bills to pay than money to pay them with, the owner will need to make tough decisions. It can be easy to forget about or ignore amounts due to vendors, but this problem is compounded when it occurs with more and more vendors. Ultimately, it can get to the point where vendors will no longer sell to you on credit, or even at all. When a company can no longer buy inventory to sell to customers, it won’t be long until it’s out of business. An ethical entrepreneur will be alert to this concern and resolve it with aboveboard business decisions.
How Bootstrapping Helps
Although bootstrapping can be painful in the early years of a business, it yields significant benefits for the business owner in the long term. One of the most valued benefits of bootstrapping a business is the fact that the founder can maintain control of the company and typically retain 100 percent ownership. Although it can be easy to give up ownership in an idea because ideas come freely and don’t require financial sacrifice, entrepreneurs who accept an equity financing opportunity and give up a significant portion of ownership of the business may not realize the potential detrimental outcomes. What seems glamorous on Shark Tank may cost a business owner more control than desired. Once you give up any amount of equity in a business, it can be difficult or expensive to get it back. Once the deal is accepted, the investor is entitled to that percentage of the profit every year the company is in business, even if that person never lifts a finger to support the enterprise. Entrepreneurs usually make those financing deals because of the benefits of the money and access to the investor’s contacts. It’s unlikely that Mark Cuban is going to roll up his sleeves in your food truck when things get tough. If you can avoid outside financing, you will maintain complete control and full ownership of the business, and you should weigh this benefit in your financing decisions.
Another benefit of bootstrapping is avoiding taking on debt. Whether it’s in the form of credit cards or personal loans, repayment of debt can take a serious toll on any business and can be especially burdensome for new businesses. Considering that some of the debt financing sources available to entrepreneurs can bear higher-than-average interest rates, digging yourself out from underneath this financial burden is no easy task. Also, delaying outside investments allows your business to grow not only in revenue and profit, but also in market value. When potential investors come along, they will consider a higher contribution for a smaller percentage of the business.
LINK TO LEARNING
One of the most common forms of debt financing is simply a credit card. Although it may seem wise to charge many of the upfront expenses and simply pay the card’s minimum monthly payment, this can be a treacherous road to go down. Try the credit card calculator to calculate how long it takes to pay off a credit using only the minimum payment. It may shock you. Try a few different amounts: $1,000; $5,000; and $10,000.


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15.1: Color Codes and Contrasts
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Link color
is hsl(199, 97%, 33%) #0372a6
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Hover color of link is hsl(356, 79%, 42%);
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Background is white hsl(0, 0%, 100%)
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Surrounding text is hsl(0, 0%, 0%)
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Link to white background: 5.3
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Hover Link to white Background: 6.21
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Link to surrounding text: 3.96
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Surrounding text to background: 21
Definition/Procedure/Theorem: Word (left)
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Link color
is hsl(199, 97%, 33%)
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Hover color of link is hsl(356, 79%, 42%);
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green background is hsl(124, 33%, 94%)
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Surrounding text is hsl(0, 0%, 0%)
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Link to green background: 4.74
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Hover Link to green Background: 5.56
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Link to surrounding text: 3.96
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Surrounding text to background: 18
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Background to white: 1.11
Example/Exercise/Note \(\PageIndex{1}\)
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Link color
is hsl(199, 97%, 33%)
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Hover color of link is hsl(356, 79%, 42%);
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blue background is hsla(204, 83%, 97%)
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Surrounding text is hsl(0, 0%, 0%)
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Link to blue background: 4.97;
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Hover Link to blue Background: 5.83
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Link to surrounding text: 3.96
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Surrounding text to background: 19.72
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Background to white: 1.06
Caution
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Link color
is hsl(199, 97%, 33%)
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Hover color of link is hsl(356, 79%, 42%)
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remove
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red background is hsl(0, 100%, 96%)
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Surrounding text is hsl(0, 0%, 0%)
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Link to red background: 4.62
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Hover Link to red Background: 5.42
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Link to surrounding text: 3.96
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Surrounding text to background: 18.33
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Background to white: 1.14


15.5: Acid-Base Balance
As with electrolytes, correct balance of acids and bases in the body is essential to proper body functioning. Even a slight variance outside of normal can be life-threatening, so it is important to understand normal acid-base values, as well their causes and how to correct them. The kidneys and lungs work together to correct slight imbalances as they occur. As a result, the kidneys compensate for shortcomings of the lungs, and the lungs compensate for shortcomings of the kidneys.
Arterial Blood Gases
Arterial blood gases (ABG) are measured by collecting blood from an artery, rather than a vein, and are most commonly collected via the radial artery. ABGs measure the pH level of the blood, the partial pressure of arterial oxygen (PaO2), the partial pressure of arterial carbon dioxide (PaCO2), the bicarbonate level (HCO3), and the oxygen saturation level (SaO2).
Prior to collecting blood gases, it is important to ensure the patient has appropriate arterial blood flow to the hand. This is done by performing the Allen test. When performing the Allen test, pressure is held on both the radial and ulnar artery below the wrist. Pressure is released from the ulnar artery to check if blood flow is adequate. If arterial blood flow is adequate, warmth and color should return to the hand.
pH
pH is a scale from 0-14 used to determine the acidity or alkalinity of a substance. A neutral pH is 7, which is the same pH as water. Normally, the blood has a pH between 7.35 and 7.45. A blood pH of less than 7.35 is considered acidic, and a blood pH of more than 7.45 is considered alkaline.
The pH of blood is a measure of hydrogen ion concentration. A low pH, less than 3.5, occurs in acidosis when the blood has a high hydrogen ion concentration. A high pH, greater than 7.45, occurs in alkalosis when the blood has a low hydrogen ion concentration. Hydrogen ions are by-products of the metabolism of substances such as proteins, fats, and carbohydrates. These by-products create extra hydrogen ions (H+) in the blood that need to be balanced and kept within normal range as described earlier.
The body has several mechanisms for maintaining blood pH. The lungs are essential for maintaining pH and the kidneys also play a role. For example, when the pH is too low (i.e., during acidosis), the respiratory rate quickly increases to eliminate acid in the form of carbon dioxide (CO2). The kidneys excrete additional hydrogen ions (acid) in the urine and retain bicarbonate (base). Conversely, when the pH is too high (i.e., during alkalosis), the respiratory rate decreases to retain acid in the form of CO2. The kidneys excrete bicarbonate (base) in the urine and retain hydrogen ions (acid).
PaCO2
PaCO2 is the partial pressure of arterial carbon dioxide in the blood. The normal PaCO2 level is 35-45 mmHg. CO2 forms an acid in the blood that is regulated by the lungs by changing the rate or depth of respirations.
As the respiratory rate increases or becomes deeper, additional CO2 is removed causing decreased acid (H+) levels in the blood and increased pH (so the blood becomes more alkaline). As the respiratory rate decreases or becomes more shallow, less CO2 is removed causing increased acid (H+) levels in the blood and decreased pH (so the blood becomes more acidic).
Generally, the lungs work quickly to regulate the PaCO2 levels and cause a quick change in the pH. Therefore, an acid-base problem caused by hypoventilation can be quickly corrected by increasing ventilation, and a problem caused by hyperventilation can be quickly corrected by decreasing ventilation. For example, if an anxious patient is hyperventilating, they may be asked to breathe into a paper bag to rebreathe some of the CO2 they are blowing off. Conversely, a postoperative patient who is experiencing hypoventilation due to the sedative effects of receiving morphine is asked to cough and deep breathe to blow off more CO2.
HCO3
HCO3 is the bicarbonate level of the blood and the normal range is 22-26. HCO3 is a base managed by the kidneys and helps to make the blood more alkaline. The kidneys take longer than the lungs to adjust the acidity or alkalinity of the blood, and the response is not visible upon assessment. As the kidneys sense an alteration in pH, they begin to retain or excrete HCO3, depending on what is needed. If the pH becomes acidic, the kidneys retain HCO3 to increase the amount of bases present in the blood to increase the pH. Conversely, if the pH becomes alkalotic, the kidneys excrete more HCO3, causing the pH to decrease.
PaO2
PaO2 is the partial pressure of arterial oxygen in the blood. It more accurately measures a patient’s oxygenation status than SaO2 (the measurement of hemoglobin saturation with oxygen). Therefore, ABG results are also used to manage patients in respiratory distress.
Read more information about interpreting ABG results in the “ Oxygen Therapy ” chapter in Open RN Nursing Skills .
See Table 15.5a for a review of ABG components, normal values, and key critical values. A critical ABG value means there is a greater risk of serious complications and even death if not corrected rapidly. For example, a pH of 7.10, a shift of only 0.25 below normal, is often fatal because this level of acidosis can cause cardiac or respiratory arrest or significant hyperkalemia. [1] As you can see, failure to recognize ABG abnormalities can have serious consequences for your patients.
| ABG Component | Description | Adult Normal Value | Critical Value |
|---|---|---|---|
| pH |
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7.35-7.45 |
<7.25
>7.60 |
| PaO2 |
|
80-100 mmHg | <60 mmHg |
| PaCO2 |
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35-45 mmHg |
<25 mmHg
>60 mmHg |
| HCO3 |
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22-26 mEq/L |
<10 mEq/L
>40 mEq/L |
| SaO2 |
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95-100% | <88% |
Interpreting Arterial Blood Gases
After the ABG results are received, it is important to understand how to interpret them. A variety of respiratory, metabolic, electrolyte, or circulatory problems can cause acid-base imbalances. Correct interpretation also helps the nurse and other health care providers determine the appropriate treatment and evaluate the effectiveness of interventions.
Arterial blood gasses can be interpreted as one of four conditions: respiratory acidosis, respiratory alkalosis, metabolic acidosis, or metabolic alkalosis. Once this interpretation is made, conditions can further be classified as compensated, partially compensated, or uncompensated. A simple way to remember how to interpret ABGs is by using the ROME method of interpretation, which stands for R espiratory O pposite, M etabolic E qual. This means that the respiratory component (PaCO2) moves in the opposite direction of the pH if the respiratory system is causing the imbalance. If the metabolic system is causing the imbalance, the metabolic component (HCO3) moves in the same direction as the pH. Some nurses find the Tic-Tac-Toe method of interpretation helpful. If you would like to learn more about this method, click on the hyperlink below to view a video.
Respiratory Acidosis
Respiratory acidosis develops when carbon dioxide (CO2) builds up in the body (referred to as hypercapnia ), causing the blood to become increasingly acidic. Respiratory acidosis is identified when reviewing ABGs and the pH level is below 7.35 and the PaCO2 level is above 45, indicating the cause of the acidosis is respiratory. Note that in respiratory acidosis, as the PaCO2 level increases, the pH level decreases. Respiratory acidosis is typically caused by a medical condition that decreases the exchange of oxygen and carbon dioxide at the alveolar level, such as an acute asthma exacerbation, chronic obstructive pulmonary disease (COPD), or an acute heart failure exacerbation causing pulmonary edema. It can also be caused by decreased ventilation from anesthesia, alcohol, or administration of medications such as opioids and sedatives.
Chronic respiratory diseases, such as COPD, often cause chronic respiratory acidosis that is fully compensated by the kidneys retaining HCO3. Because the carbon dioxide levels build up over time, the body adapts to elevated PaCO2 levels so they are better tolerated. However, in acute respiratory acidosis, the body has not had time to adapt to elevated carbon dioxide levels, causing mental status changes associated with hypercapnia. Acute respiratory acidosis is caused by acute respiratory conditions, such as an asthma attack or heart failure exacerbation with pulmonary edema when the lungs suddenly are not able to ventilate adequately. As breathing slows and respirations become shallow, less CO2 is excreted by the lungs and PaCO2 levels quickly rise.
Signs of symptoms of hypercapnia vary depending upon the level and rate of CO2 accumulation in arterial blood:
- Patients with mild to moderate hypercapnia may be anxious and/or complain of mild dyspnea, daytime sluggishness, headaches, or hypersomnolence.
- Patients with higher levels of CO2 or rapidly developing hypercapnia develop delirium, paranoia, depression, and confusion that can progress to seizures and coma as levels continue to rise.
Individuals with normal lung function typically exhibit a depressed level of consciousness when the PaCO2 is greater than 75 to 80 mmHg, whereas patients with chronic hypercapnia may not develop symptoms until the PaCO2 rises above 90 to 100 mmHg. [5]
When a patient demonstrates signs of potential hypercapnia, the nurse should assess airway, breathing, and circulation. Urgent assistance should be sought, especially if the patient is in respiratory distress. The provider will order an ABG and prescribe treatments based on assessment findings and potential causes. Treatment for respiratory acidosis typically involves improving ventilation and respiration by removing airway restrictions, reversing oversedation, administering nebulizer treatments, or increasing the rate and depth of respiration by using a BiPAP or CPAP devices. BiPAP and CPAP devices provide noninvasive positive pressure ventilation to increase the depth of respirations, remove carbon dioxide, and oxygenate the patient. If these noninvasive interventions are not successful, the patient is intubated and placed on mechanical ventilation. [6] , [7]
Respiratory Alkalosis
Respiratory alkalosis develops when the body removes too much carbon dioxide through respiration, resulting in increased pH and an alkalotic state. When reviewing ABGs, respiratory alkalosis is identified when pH levels are above 7.45 and the PaCO2 level is below 35. With respiratory alkalosis, notice that as the PaCO2 level decreases, the pH level increases.
Respiratory alkalosis is caused by hyperventilation that can occur due to anxiety, panic attacks, pain, fear, head injuries, or mechanical ventilation. Overdoses of salicylates and other toxins can also cause respiratory alkalosis initially and then often progress to metabolic acidosis in later stages. Acute asthma exacerbations, pulmonary embolisms, or other respiratory disorders can initially cause respiratory alkalosis as the lungs breath faster in an attempt to increase oxygenation, which decreases the PaCO2. After a while, however, these hypoxic disorders cause respiratory acidosis as respiratory muscles tire, breathing slows, and CO2 builds up in the blood.
Patients experiencing respiratory alkalosis often report feelings of shortness of breath, dizziness or light-headedness, chest pain or tightness, paresthesias, and palpitations as a result of decreased carbon dioxide levels. [8] Respiratory alkalosis is not fatal, but it is important to recognize that underlying conditions such as an asthma exacerbation or pulmonary embolism can be life-threatening, so treatment of these underlying conditions is essential. As the pH level increases, the kidneys will attempt to compensate for the shortage of H+ ions by reabsorbing HCO3 before it can be excreted in the urine. This is a slow process, so additional treatment may be necessary.
Treatment of respiratory alkalosis involves treating the underlying cause of the hyperventilation. Acute management of patients who are hyperventilating should focus on patient reassurance, an explanation of the symptoms the patient is experiencing, removal of any stressors, and initiation of breathing retraining. Breathing retraining attempts to focus the patient on abdominal (diaphragmatic) breathing. Read more about breathing retraining in the following box.
While sitting or lying supine, the patient should place one hand on their abdomen and the other on the chest, and then be asked to observe which hand moves with greater excursion. In hyperventilating patients, this will almost always be the hand on the chest. Ask the patient to adjust their breathing so that the hand on the abdomen moves with greater excursion and the hand on the chest barely moves at all. Assure the patient that this is hard to learn and will take some practice to fully master. Ask the patient to breathe in slowly over four seconds, pause for a few seconds, and then breathe out over a period of eight seconds. After 5 to 10 such breathing cycles, the patient should begin to feel a sense of calmness with a reduction in anxiety and an improvement in hyperventilation. Symptoms should ideally resolve with continuation of this breathing exercise.
If the breathing retraining technique is not successful in resolving a hyperventilation episode and severe symptoms persist, the patient may be prescribed a small dose of a short-acting benzodiazepine (e.g., lorazepam 0.5 to 1 mg orally or 0.5 to 1 mg intravenously). Current research indicates that instructing patients who are hyperventilating to rebreathe carbon dioxide (CO2) by breathing into a paper bag can cause significant hypoxemia with significant complications, so this intervention is no longer recommended. If rebreathing is used, oxygen saturation levels should be continuously monitored. [9]
Metabolic Acidosis
Metabolic acidosis occurs when there is an accumulation of acids (hydrogen ions) and not enough bases (HCO3) in the body. Under normal conditions, the kidneys work to excrete acids through urine and neutralize excess acids by increasing bicarbonate (HCO3) reabsorption from the urine to maintain a normal pH. When the kidneys are not able to perform this buffering function to the level required to excrete and neutralize the excess acid, metabolic acidosis results.
Metabolic acidosis is characterized by a pH level below 7.35 and an HCO3 level below 22 when reviewing ABGs. It is important to notice that both the pH and HCO3 decrease with metabolic acidosis (i.e., the pH and HCO3 move in the same downward direction). A common cause of metabolic acidosis is diabetic ketoacidosis, where acids called ketones build up in the blood when blood sugar is extremely elevated. Another common cause of metabolic acidosis in hospitalized patients is lactic acidosis, which can be caused by impaired tissue oxygenation. Metabolic acidosis can also be caused by increased loss of bicarbonate due to severe diarrhea or from renal disease that causes decreased acid elimination. Additionally, toxins such as salicylate excess can cause metabolic acidosis. [10]
Nurses may first suspect that a patient has metabolic acidosis due to rapid breathing that occurs as the lungs try to remove excess CO2 in an attempt to resolve the acidosis. Other symptoms of metabolic acidosis include confusion, decreased level of consciousness, hypotension, and electrolyte disturbances that can progress to circulatory collapse and death if not treated promptly. It is important to quickly notify the provider of suspected metabolic acidosis so that an ABG can be drawn and treatment prescribed (based on the cause of the metabolic acidosis) to allow acid levels to improve. Treatment includes IV fluids to improve hydration status, glucose management, and circulatory support. When pH drops below 7.1, IV sodium bicarbonate is often prescribed to help neutralize the acids in the blood. [11] , [12]
Metabolic Alkalosis
Metabolic alkalosis occurs when there is too much bicarbonate (HCO3) in the body or an excessive loss of acid (H+ ions). Metabolic alkalosis is defined by a pH above 7.45 and an HCO3 level above 26 on ABG results. Note that both pH and HCO3 are elevated in metabolic alkalosis.
Metabolic alkalosis can be caused by gastrointestinal loss of hydrogen ions, excessive urine loss, excessive levels of bicarbonate, or a shift of hydrogen ions from the bloodstream into cells.
Prolonged vomiting or nasogastric suctioning can also cause metabolic alkalosis. Gastric secretions have high levels of hydrogen ions (H+), so as acid is lost, the pH level of the bloodstream increases.
Excessive urinary loss (due to diuretics or excessive mineralocorticoids) can cause metabolic alkalosis due to loss of hydrogen ions in the urine. Intravenous administration of sodium bicarbonate can also cause metabolic alkalosis due to increased levels of bases introduced into the body. Although it was once thought that excessive intake of calcium antacids could cause metabolic alkalosis, it has been found that this only occurs if they are administered concurrently with Kayexelate. [13]
Hydrogen ions may shift into cells due to hypokalemia, causing metabolic alkalosis. When hypokalemia occurs (i.e., low levels of potassium in the bloodstream), potassium shifts out of cells and into the bloodstream in an attempt to maintain a normal level of serum potassium for optimal cardiac function. However, as the potassium (K+) molecules move out of the cells, hydrogen (H+) ions then move into the cells from the bloodstream to maintain electrical neutrality. This transfer of ions causes the pH in the bloodstream to drop, causing metabolic alkalosis. [14]
A nurse may first suspect that a patient has metabolic alkalosis due to a decreased respiratory rate (as the lungs try to retain additional CO2 to increase the acidity of the blood and resolve the alkalosis). The patient may also be confused due to the altered pH level. The nurse should report signs of suspected metabolic alkalosis because uncorrected metabolic alkalosis can result in hypotension and cardiac dysfunction. [15]
Treatment is prescribed based on the ABG results and the suspected cause. For example, treat the cause of the vomiting, stop the gastrointestinal suctioning, or stop the administration of diuretics. If hypokalemia is present, it should be treated. If bicarbonate is being administered, it should be stopped. Patients with kidney disease may require dialysis. [16]
Analyzing ABG Results
Now that we’ve discussed the differences between the various acid-base imbalances, let’s review the steps to systematically interpret ABG results. Table 15.5b outlines the steps of ABG interpretation.
| Step | Action |
|---|---|
| Step 1: pH (normal 7.35-7.45) |
If pH is out of range, determine if it is acidosis or alkalosis:
|
| Step 2: PaCO2 (normal 35-45 mmHg) |
**If the imbalance does not appear to be caused by a respiratory problem, move on to evaluate the HCO3. |
| Step 3: HCO3 (normal 22-26) |
|
| Step 4: Determine level of compensation |
After determining the cause of the pH imbalance, determine if compensation is occurring.
|
- Mitchel, J. H., Wildenthal, K., & Johnson Jr., R. L. (1972). The effects of acid-base disturbances on cardiovascular and pulmonary function. Kidney International, 1 , 375-389. https://www.kidney-international.org/article/S0085-2538(15)31047-4/pdf ↵
- WakeMed Pathology Laboratories. (2016). Critical values . https://www.wakemed.org/assets/documents/pathology/lab-critical-values.pdf ↵
- Forciea, B. (2017, May 10). Acid-base balance: Bicarbonate ion buffer . [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/5_S5wZks9v8 ↵
- RegisteredNurseRN. (2015, May 6). ABGs made easy for nurses w/ tic tac toe method for arterial blood gas interpretation . [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/URCS4t9aM5o ↵
- Feller-Kopman, D. J., & Schwartzstein, R. M. (2020). The evaluation, diagnosis, and treatment of the adult patient with acute hypercapnic respiratory failure. UpToDate . https://www.uptodate.com/contents/the-evaluation-diagnosis-and-treatment-of-the-adult-patient-with-acute-hypercapnic-respiratory-failure ↵
- A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Respiratory acidosis; [updated 2021, February 8]. https://medlineplus.gov/ency/article/000092.htm ↵
- Feller-Kopman, D. J., & Schwartzstein, R. M. (2020). The evaluation, diagnosis, and treatment of the adult patient with acute hypercapnic respiratory failure. UpToDate . https://www.uptodate.com/contents/the-evaluation-diagnosis-and-treatment-of-the-adult-patient-with-acute-hypercapnic-respiratory-failure ↵
- Schwartzstein, R. M., Richards, J., Edlow, J. A., & Roy-Byrne, P. P. (2020). Hyperventilation syndrome in adults. UpToDate . https://www.uptodate.com/contents/hyperventilation-syndrome-in-adults ↵
- Schwartzstein, R. M., Richards, J., Edlow, J. A., & Roy-Byrne, P. P. (2020). Hyperventilation syndrome in adults. UpToDate . https://www.uptodate.com/contents/hyperventilation-syndrome-in-adults ↵
- Emmett, M., & Szerlip, H. (2020). Approach to the adult with metabolic acidosis. UpToDate . https://www.uptodate.com/contents/approach-to-the-adult-with-metabolic-acidosis ↵
- A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Metabolic acidosis; [updated 2021, February 8]. https://medlineplus.gov/ency/article/000335.htm ↵
- Emmett, M., & Szerlip, H. (2020). Approach to the adult with metabolic acidosis. UpToDate . https://www.uptodate.com/contents/approach-to-the-adult-with-metabolic-acidosis ↵
- Emmett, M., & Szerlip, H. (2020). Causes of metabolic alkalosis. UpToDate . https://www.uptodate.com/contents/causes-of-metabolic-alkalosis ↵
- Emmett, M., & Szerlip, H. (2020). Causes of metabolic alkalosis. UpToDate . https://www.uptodate.com/contents/causes-of-metabolic-alkalosis ↵
- This work is a derivative of StatPearls by Brinkman and Sharma and is licensed under CC BY 4.0 ↵
- Emmett, M., & Szerlip, H. (2020). Causes of metabolic alkalosis. UpToDate . https://www.uptodate.com/contents/causes-of-metabolic-alkalosis ↵
- This work is a derivative of StatPearls by Castro and Keenaghan and is licensed under CC BY 4.0 ↵
- Woodruff, D. W. (2012). 6 easy steps to ABG analysis . Ed4Nurses, Inc. http://www.profcaseyscudmorern.org/uploads/4/5/0/4/45049193/abgebook.pdf ↵