15.4: Quoting
- Effectively integrate and introduce quotes into text
Now that you’ve thought about source integration broadly, it’s time to explore the three main tools for integrating source content into your own writing: quoting, paraphrasing, and summarizing. You’ve probably used direct quotations in your papers before, but did you know that you should only use quotations in your paper under certain conditions? Summary and paraphrase of source material can also be effective, often instead of direct quotations. First, however, let’s take a closer look at when and how to use a direct quote.
What Does Quotation Look Like?
Direct quotations are words and phrases that are taken directly from another source and then used word-for-word in your paper. Quoting is using the EXACT wording of the source material. If you incorporate a direct quotation from another author’s text, you must put that quotation or phrase in quotation marks to indicate that it is not your language.
When writing direct quotations, you can use the source author’s name in the same sentence as the quotation to introduce the quoted text and to indicate the source in which you found the text. You should then include the page number or other relevant information in parentheses at the end of the phrase (the exact format will depend on the formatting style of your essay).
When writing papers that require the use of outside source material, it is often tempting to cite only direct quotations from your sources. The danger, however, is that your paper will become nothing more than a series of quotations linked together by a few connecting words. Your paper may seem to be a collection of others’ thoughts, with little thinking on your part. To avoid falling into this trap, follow a few simple pointers:
- Avoid using long quotations merely as space-fillers . While this is an attractive option when faced with a ten-page paper, the overuse of long quotations gives the reader the impression you are not thinking for yourself.
- Don’t use quotations to make your point for you . Readers should be able to skip the quotations in your paper and still understand all your main points.
- Use only as much of the quotation as you need. Excerpt from the source material and leave out any unnecessary words.
- When introducing direct quotations, try to use a variety of verbs in your signal phrases . Don’t always rely on stock verbs such as “states” or “says.” Think for a little while about the purpose of your quotation and then choose a context-appropriate verb.
- Finally, don’t use only direct quotations . Try using paraphrases in addition to direct quotations. To the reader, the effective use of paraphrases indicates that you took the time to think about the meaning behind the quotation’s words.
Direct quotations should be used sparingly and only with good reason! Some valid reasons for quoting include:
- When not using the author’s exact wording would change the original meaning
- When the language of the quote is particularly significant
- To lend authority to the point you are trying to make
Quoting Words and Parts of Sentences
Although you generally want to avoid using too many short quotes when you write, there are times when you need to quote just a word or a phrase as a part of your own sentence. Short phrases and single words should work smoothly with the structure of your own sentence. Look, for example, at the way the brief passages from Thoreau’s Walden aid in the flow and credibility of this sentence:
- The demands of a market economy, in fact, would penalize a man who chose to give precedence to relationships and “true integrity” over labor: an over-emphasis on work leaves a man dehumanized and with “no time to be anything but a machine” (Thoreau 21).
Block Quotations and Ellipses
Long quotations should be kept to a minimum in your essay. Additionally, you should only use those parts of the long quotation that you really need. If a passage has a middle section that doesn’t relate to the point you are making, drop it out and replace it with an ellipsis (…) to indicate that you have left out part of the original text (see below).
Set up long quotations in blocks; these are generally called block quotations. Block quotations are most often used if the passage takes up more than four typed lines in your paper. Indentation and spacing guidelines vary depending on the formatting style you are using (APA, MLA, Chicago, or other).
Leave the quotation marks off of a block quotation. The indentation itself is the visual indicator to the reader that the text is a quote. Block quotations usually are introduced with a full sentence that summarizes the main point of the quotation. This introductory sentence should be followed by a colon, as in the example below.
Henry David Thoreau argued in Walden that men who are over-occupied with labor run the risk of becoming dehumanized. They must be granted the time to learn about, and address, their own shortcomings in order to fully mature as humans:
He has not time to be anything but a machine. How can he remember well his ignorance–which his growth requires–who has so often to use his knowledge? We should feed and clothe him gratuitously sometimes, and recruit him with our cordials, before we judge of him. The finest qualities of our nature, like the bloom on fruits, can be preserved only by the most delicate handling. (23)
Here’s the same block quote with an ellipsis to indicate the removal of a bit of unnecessary text from the source material. The use of an ellipsis is particularly effective if the original quotation includes unnecessary or potentially confusing language.
He has not time to be anything but a machine. How can he remember well his ignorance . . . who has so often to use his knowledge? We should feed and clothe him gratuitously sometimes, and recruit him with our cordials, before we judge of him. The finest qualities of our nature, like the bloom on fruits, can be preserved only by the most delicate handling. (23)
It’s important to remember that longer quotes should be set up and followed by commentary and analysis, just like shorter quotes. Be sure to provide some analysis after that quote to let your audience know why the quote is there and why it’s important. Otherwise, long quotes can look and feel like “filler” to your audience.
Brackets
If you need to add information to make a quote more clear, you add brackets to show your reader which words you have added. Let’s take a look at an example.
Suppose you are including a quotation from an essay about the importance of finding a mentor in college. The particular sentence you are interested in reads as follows: “There is nothing more important to your success during and after college” (Purple 23). If you were to quote this sentence, the reader would have no idea what exactly is being recommended here. We could address this lack of clarity with information added outside the quotation, but we could also use brackets to add clarifying information inside the quotation.
- “There is nothing more important to your success during and after college” (Purple 23) than finding a mentor.
- “There is nothing more important [than finding a mentor] to your success during and after college” (Purple 23).
The brackets here make clear that “than finding a mentor” are words we have added to the quotation. The added words need to reflect and clarify the meaning of the original quotation but they can also help make our use of the quotation more graceful.
Here are a few other common uses for brackets:
“[N]othing,” according to Purple, is “more important to your success during and after college” (23) than finding a mentor. Here the brackets make clear that the capital N to start the sentence is our own, not Purple’s.
“There is nothing more important to your [academic and career] success during and after college” (Purple 23) than finding a mentor. Here we use the brackets to clarify what Purple means by success, again using our own words in brackets.
Be careful: [Brackets] are different from (parentheses). Don’t get them mixed up! We use brackets when we are adding additional text but parentheses for parenthetical citations of sources (which we’ll be discussing later).
Contributors and Attributions
- Introduction, revision, and adaptation. Provided by : University of Mississippi. License : CC BY: Attribution
- Using Sources in Your Writing. Provided by : Lumen Learning. Located at : courses.lumenlearning.com/engcomp1-wmopen/chapter/text-using-sources-in-your-writing/. License : CC BY-NC-SA: Attribution-NonCommercial-ShareAlike
- Incorporating Your Sources Into Your Paper. Provided by : Boundless. Located at : courses.lumenlearning.com/boundless-writing/. Project : Boundless Writing. License : CC BY-SA: Attribution-ShareAlike
- Block Quotations. Provided by : Excelsior OWL. Located at : https://owl.excelsior.edu/research/drafting-and-integrating/drafting-and-integrating-using-quotations/long-quotations/ . License : CC BY: Attribution
- Image of coffee mug. Authored by : Bryce Koch. Provided by : Unsplash. Located at : https://unsplash.com/photos/KGedrLRVMQo . License : Other . License Terms : https://unsplash.com/license
- Synthesizing What You Read. Provided by : Excelsior Online Reading Lab. Located at : https://owl.excelsior.edu/orc/what-to-do-after-reading/synthesizing/ . License : CC BY: Attribution


11.2: Quantum Numbers of Multielectron Atoms
The quantum numbers of atoms (and ions) correspond to quantized energy states, called microstates, that depend on the electron configuration. Electrons within a subshell or orbital can adopt different configurations of their electrons, with different individual quantum numbers. These different electron configurations are microstates , and they can be grouped into terms and ordered according to their relative energies. Since electronic transitions occur between terms of different energies, knowledge of the terms for a given atom or ion can aid in the interpretation of electronic spectra.
Introduction
Transition metal ions can give rise to a spectrum of beautifully colored colored complexes. The colors are often caused by absorption of visible light due to electronic transitions involving metal d-orbitals. These electronic transitions are not only attractive to the eye, they are useful spectroscopic signals because the transitions occur between quantized electronic energy states, called microstates. Spectroscopy, coupled with knowledge of the possible microstates and their energies can yield clues about molecular structure.
To learn what a microstate is, let's use the simple example of a carbon atom with a \(1s^2 2s^2 2p^2\) electron configuration. The \(s\) subshell is full, and there is only one way to put two electrons into an \(s\) subshell. Both electrons must occupy the orbital having \(m_l=0\), and each must have opposite spins, (\(m_s =+\frac{1}{2}\)), and (\(m_s =-\frac{1}{2}\)). On the other hand, the \(p\) subshell of carbon has two electrons that can occupy any of three orbitals (Figure \(\PageIndex{1}\)). This leaves room for different orientations of the electrons within the \(p\) subshell. Each different electron configuration is a microstate , and each has an energy that can be distinguished using electronic spectroscopy (UV-vis for example). In the case of a carbon atom with a two \(p\) electrons, there are 15 different possible microstates, as illustrated in Figure \(\PageIndex{1}\).
Just as individual electrons have quantum numbers (\(n, l, m_l, m_s\)), the electronic states of atoms have quantum numbers (\(L, M_l, M_s, S, J\)). Each individual microstate in Figure \(\PageIndex{1}\) can be described by quantum numbers \(M_l\) and \( M_s\). The values of total angular momentum (\(L\)), and total intrinsic spin (\(S\)) arise from sets of microstates, and are related to quantum numbers \(M_l\) and \(M_s\) for individual microstates. The relative energies of the terms for 3d metals and other light atoms can be predicted (roughly) by Hund's Rules, according to values of S and L. These atomic quantum numbers and Hund's rules are described below.
A closer look at electronic spectra
Let us take a closer look at optical absorption spectra, also called electronic spectra, of coordination compounds. We have previously argued that ligand field theory can predict and explain the electronic spectra. However, ligand field theory (LFT) is sufficient to explain the spectra in only a few cases. For example the \(\ce{[Ni(H2O)6]^2+}\) ion is an octahedral \(d^8\)-complex ion. According to LFT, the metal \(d\)-orbitals in an octahedral field are the \(t_{2g}\) and the \(e_g\)–orbitals (Figure \(\PageIndex{2}\)). Six electrons are in the \(t_{2g}\) orbitals, and two electrons are in the \(e_{g}\) orbitals (Figure \(\PageIndex{2}\)). Ligand field theory (LFT) would predict that there is one electron transition possible, namely the promotion of an electron from a \(t_{2g}\) into an \(e_{g}\) orbital. This process would be triggered by the absorption of light whereby the wavelength of the light would depend on the \(\Delta_o\) between the \(t_{2g}\) and the \(e_{g}\) orbitals. Overall, this should lead to a single absorption band in the absorption spectrum of the complex. We can check this prediction by experimentally recording the absorption spectrum of the complex (Figure \(\PageIndex{2}\)).
What we find is that the absorption spectrum is far more complex than expected. Instead of just a single absorption band there are multiple ones. Obviously, LFT is unable to explain this spectrum. The question is: why? The answer is: LFT assumes that there are no electron-electron interactions. However, in reality there is repulsion between electron in d-orbitals and this has an effect on their energy. And, electrons within the d-subshell, for example, repel each other to different extents depending on the relative orientations of their orbitals in space.
To illustrate how electrons in different orbitals might have different interactions, let's consider the case of a \(d^2\) excited state in an octahedral ligand field (Figure \(\PageIndex{3}\)).
According to LFT, both electrons would be in the \(t_{2g}\) orbitals in the ground state. For instance, they could be in the microstate where one electron is in \(d_{xy}\), and the other is in the \(d_{xz}\) orbital (not pictured). This configuration is called a microstate of a state because there are other combinations of orbitals possible. For example, the ground state would also be realized by a microstate in which the electrons were in the \(d_{xz}\) and the \(d_{yz}\) orbitals. Upon absorption of light, the electron in the \(d_{xy}\) orbital could be excited into one of the higher-energy \(e_{g}\) orbitals. That excited electron could occupy either the \(d_{z^2}\) or the \(d_{x^2-y^2}\) orbitals. Those two possibilities reflect two different microstates associated with the excited state. For a moment, let's assume that the excited electron goes into the \(d_{z^2}\) orbital. In this microstate one electron would be in the \(d_{xz}\) orbital and the other one in the \(d_{z^2}\) orbital (Figure \(\PageIndex{3}\), right). There is another possibility for how to excite an electron from the ground state. We could assume that instead of the \(d_{xy}\) electron being promoted, the \(d_{xz}\) electron gets promoted. In this case, we would realize a microstate in which one electron in the \(d_{xy}\) orbital and the other one in the \(d_{z^2}\) orbital (Figure \(\PageIndex{3}\), left).
Now let us compare the two cases shown in Figure \(\PageIndex{3}\). Ligand field theory would argue that both excited microstates have the same energy. However, in fact they do not. Why? It is because the electrons in the first excited microstate interact differently than those of the second excited microstate. This difference becomes plausible when considering the orbital shapes and orientations (Figure \(\PageIndex{3}\), bottom). The \(d_{xz}\) orbital has electron density on the z-axis, while the \(d_{xy}\) orbital is perpendicular to \(d_{z^2}\). The different relative orientations of \(d_{xy}\) and \(d_{xz}\) with respect to \(d_{z^2}\) cause electrons in the \(d_{z^2}\) orbital to interact differently with an electron in a \(d_{xy}\) than in a \(d_{xz}\). As a result, the two excited microstates do not have the same energy. In other words, to achieve either of these different excited microstates from the ground state, we need different amounts of energy. Thus, the complex would absorb light with different energies (or wavelengths). This is in contrast to what LFT predicts.
If LFT cannot predict the number of electronic transitions, then how can we correctly predict how many absorption bands we get? The answer is, we must find all possible microstates for the \(d^2\) electron configuration and group together those with the same energy. A group of microstates with the same energy is called a term . The number of electron transitions can then be predicted from the number of terms.
Quantum Numbers
The table below summarizes the quantum numbers of atoms (individual microstates and sets of microstates). You may wish to review the quantum numbers for individual electrons and then refer to this table as you read this and the next sections. Recall the meanings of the quantum numbers for individual electrons (\(n, l, m_l, m_s\) that were described in a previous section ( Section 2.2.2 ).
| Symbol | Name | Allowed Range | Comment |
|---|---|---|---|
| \(L\) | Total Orbital Angular Momentum | \(|l_1 + l_2 | , |l_1 + l_2 ‐ 1| , \ldots, |l_1 ‐ l_2 |\) | Total orbital angular momentum of a collection of microstates , designated as S, P, D, F..etc |
| \(S\) | Total Intrinsic Spin | \(|{m_s}_1 + {m_s}_2 |, |{m_s}_1 +{m_s}_2 ‐ 1| , ... ,| {m_s}_1 ‐ {m_s}_2 |\) | Total spin of a collection of microstates |
| \(M_l\) | Magnetic Quantum Number | \( L, L-1, L-2, ..., -L\) | Direction of total angular momentum for an individual microstate |
| \(M_s\) | Spin Magnetic Quantum Number | \(S, S-1, S-2, ...-S \) | Total spin of electrons for an individual microstate |
| \(J\) | Total Angular Momentum | \(L+S,..., | L-S |\) | Total angular momentum |
Quantum Numbers S and L for sets of microstates
The quantum numbers \(S\) and \(L\) represent sets of microstates. Once these values are found, they can be ordered in terms of relative energies, first according to the value of \(S\), then \(L\).
Total Orbital Angular Momentum Quantum Number: L
\(L\) gives the total sum of orbital angular momentum vectors in a multielectron atom. The possible values of \(L\) can be found from the values of \(l\) for individual electrons in the system. For example, in a system with two electrons with values of \(m_{l_1}\) and \(m_{l_2}\), the possible values of \(L\) are:
\[ L = \sum_i^n m_{l_i} = |m_{l_1} + m_{l_2} | , |m_{l_1} + m_{l_2} ‐ 1| , \ldots, |m_{l_1} ‐ m_{l_2} | \]
The absolute value symbols indicate that \(L\) cannot be a negative value. The values of \(L\) correspond to different energy levels for groups of microstates. Microstates with values of \(L=0, 1, 2, 3...\) correspond to symbols \(S, P, D, F...\) respectively. This is analogous to the relationship between the electron quantum number, \(l\), and the \(s, p, d, f..\) orbital subshells. However, the capital letters used for microstates do not indicate orbital or subshell assignments for the electrons.
The Total Intrinsic Spin Quantum Number: \(S\)
The sum total of the spin vectors of all of the electrons is called \(S\). The values of \(S\) are computed from \(m_s\) in a manner very similar to how \(L\) is computed from \(m_l\). Because \(S\) measures the magnitude of a vector, it cannot be negative. For a system with two electrons, each with spin \({m_s}_1\), and \({m_s}_2\), the possible values of \(S\) are given below.
\[S =\sum_i^n {m_s}_i = |{m_s}_1 + {m_s}_2 |, |{m_s}_1 +{m_s}_2 ‐ 1| , ... ,| {m_s}_1 ‐ {m_s}_2 | \label{spin}\]
The possible values of \(S\) fall into a series that depend on whether there are an odd or even number of electrons.
- Odd number of electrons: \(S=\frac{1}{2}, \frac{3}{2}, \frac{5}{2},...\)
- Even number of electrons: \(S = 0, 1, 2, 3,...\)
What are the possible \(L\) values for the electrons in the \(1s^2 2s^2 2p^2\) configuration of carbon?
Solution
Both electrons (i.e., the 2p electrons) are \(l = 1\). The possible combinations are 0, 1, and 2 corresponding to symbols S, P, and D, respectively.
What are the possible \(L\) values for the electrons in the \([Xe]6s^2 4f^1 5d^1\) ?
Solution
We can ignore the electrons in the \([Xe]\) core and the electrons in the \(6s\) block. So all we have to consider is the lone \(f\) electron (\(l=3\)) and the lone \(d\) electron (\(l=2\)).
The two extremes for possible \(L\) values are \(3+2 = 5 \) and \(3 ‐ 2 = 1\).
Thus, possible values of \(L\) for this Xe atom are 5(H), 4(G), 3(F), 2(D), and 1(P).
Find \(S\) for \(1s^1\).
Solution
\(S\) must be \(\frac{1}{2}\), since that’s the spin of a single electron and there’s only one electron.
Find S for \(1s^2 2s^1 2p^1\).
Solution
\(S = 1, 0\)
Find \(S\) for carbon atoms with the \(1s^2 2s^2 2p^2\) electron configuration.
Solution
\(S=1,0\) This is the same as the previous problem. Notice that \(S\) is not affected by which orbitals are occupied by electrons. \(S\) depends only on the number of unpaired electrons. These are usually the electrons in partially-filled subshells (i.e., unpaired electrons in open shells).
Find \(S\) for nitrogen atoms with the \(1s^2 2s^2 2p^3\) electron configuration.
Solution
\(S\) can be \(S=\frac{3}{2}, \frac{1}{2}\).
Quantum numbers \(M_l\) and \(M_s\) for individual microstates
Once S and L are found, the allowed values of \(M_l\) and \(M_s\) can be calculated.
The Total Magnetic Quantum Number: \(M_l\)
The Total Magnetic Quantum Number \(M_l\) is the total \(z\)-component of all of the relevant electrons’ orbital momentum. While \(L\) describes the total angular momentum in the system, \(M_l\) tells you which direction it is pointing. \(L\) can be assigned to a collection of microstates, but \(M_l\) is unique to a specific microstate in that group. Unlike \(L\), \(M_l\) is allowed to have negative values. The possible values of \(M_l\) are integer values ranging from the largest positive sum to the most negative sum of possible \(m_l\) values:
\[M_l = L, L-1, L-2, ..., -L \]
For the \(p^2\) case, the \(m_l\) values of \(p\) orbitals are \(-1, 0, +1\). The largest value of \(M_l\) would come from a state where both electrons occupy \(m_l=+1\), thus the maximum is \(M_l=L=2\). Likewise, the minimum value of \(M_l\) comes from both electrons occupying \(m_l=-1\) to give \(M_l=-L=-2\). The possible \(M_l\) values for \(p^2\) are the series of integer values \(+2, +1, 0, -1, -2\).
It is worth noting that there are values of \(M_l\) that are forbidden due to the Pauli exclusion principle. For example, the value of \(M_l=+3\) could only come from three electrons occupying the \(m_l=+1\) orbital. That is impossible because more than one electron would possess the same set of electron quantum numbers.
The Total Spin Magnetic Quantum Number: \(M_s\)
\(M_s\) is the sum total of the z-components of the electrons’ inherent spin in an individual microstate. The difference between \(S\) and \(M_s\) is subtle, but important. \(M_s\) indicates the total z-component of the electrons’ spins, while \(S\) indicates the entire resultant vector. It is also distinct from \(M_l\), which is the sum total of the z-component of the orbital angular momentum . \(M_s\) can be computed from \(S\), as shown below. Note that while \(S\) must be positive, \(M_s\) can have negative values.
\[M_s = S, S-1, S-2, ...-S \label{Ms}\]
For the \(p^2\) case, the possible values of \(M_s\) are \(M_s = +1, 0, -1\). The value \(M_s = +1\) comes from the sum of two electrons with spin "up", \(m_s=+\frac{1}{2}\). The value \(M_s = -1\) comes from the sum of two electrons with spin "down", \(m_s=-\frac{1}{2}\). And the value \(M_s = 0\) comes from the sum of one electron with \(m_s=+\frac{1}{2}\) and the other with \(m_s=-\frac{1}{2}\).
There are some values of \(M_s\) that will be forbidden, but not in the case of \(p^2\). However in the case of a \(p^4\), for example, the value \(M_s\)=2 is forbidden because there is no way to put four "up" electrons in three orbitals without violating the Pauli exclusion principle.
What are the possible values \(M_l\) of a zirconium atom with the \([Kr] 5s^2 4d^2\) electron configuration?
Solution
Both open-shell electrons (i.e., the 4d electrons) are \(l=2\), so the values are 4, 3, 2, 1, 0, -1, -2, -3, -4.
What are the \(M_s\) values for \(1s^2 2s^2 2p^2\) ?
Solution
This system is paramagnetic, with two unpaired electrons in the \(2p\) orbital. The three \(p\) orbitals have values of \(m_s=-1,0,1\). The maximum value of \(M_s=+1\) would come from the two electrons occupying \(m_{s_1}=+1\) and \(m_{s_2}=0\). The minimum value, \(M_s=-1\) would come from the two electrons occupying \(m_{s_1}=-1\) and \(m_{s_2}=0\). Thus, the possible values for the total spin magnetic quantum number are \(M_s = 1, 0, ‐1\), where the value of \(M_s=0\) comes from a configuration where, for example, \(m_{s_1}=+1\) and \(m_{s_2}=-1\).
What are the \(M_s\) values for \(1s^2 2s^2 2p^3\) ?
Solution
\(M_s = +\frac{3}{2}, \; +\frac{1}{2}, \; -\frac{1}{2}, \; -\frac{3}{2}\)


10.22: Outcome- Products and Marketing Mix
What you’ll learn to do: explain what a product is and the importance of products in the marketing mix
We’ll start this module by defining what a product is and seeing how it fits in the marketing mix. When thinking about the target customer’s perspective, it’s useful to have an “expansive” view of product and keep in mind that the customer experience is not only about the tangible aspects of a good.
For example, imagine that you stop at a fast-food restaurant for a quick sandwich. The sandwich is fresh and delicious and is exactly what you wanted to eat. However, the wait for the sandwich was exceptionally long, the restaurant was filthy, and the sales clerk was rude. Does that change your level of satisfaction?
Or, have you ever been excited to get a bargain on an airline ticket and then been surprised by additional fees for what seem like basic services, such as checking your luggage? Do the fees change your level of satisfaction with the product?
As we explore products and product marketing, you will find that most products include a broader range of components than you might first expect.
The specific things you’ll learn in this section include:
- Define a product
- Identify difference between products that offer goods versus services
- Explain how to augment a product with services
- Define product marketing
- Explain the role of product marketing in the marketing mix
Learning Activities
The learning activities for this section include the following:
- Reading: Defining Product
- Reading: Consumer Product Categories
- Reading: Products and Services
- Reading: Augmenting Products with Services
- Reading: Product Marketing and the Marketing Mix
- Self Check: Products and Marketing Mix
Contributors and Attributions
- Outcome: Products and Marketing Mix. Provided by : Lumen Learning. License : CC BY: Attribution


7.3: Lab Report
Part 1: Bacterial Cells
A. Fixed Slide of Bacterial Types
Draw each of the bacterial shapes in the spaces at right. Label each drawing.
B. Wet Mount of Oscillatora
Sketch the bacteria at low and high power. Label the cytoplasm and cell wall of a single cell. Draw your cells to scale.
Questions:
1. Why are nuclei not visible within the cells viewed?
2. The common name for species like Oscillatoria is blue-green algae. This group of bacteria is capable of photosynthesizing. Do they contain chloroplasts? Explain.
Part 2: Animal Cells
Procedure:
Sketch the cell at low and high power. Label the nucleus, cytoplasm, and cell membrane of a single cell. Draw your cells to scale.
Questions:
1. Why is methylene blue added?
2. The light microscope used in the lab is not powerful enough to view other organelles in the cheek cell.
a. What parts of the cell were visible?
b. List 2 organelles that were NOT visible but should have been in the cheek cell.
3. Is the cheek cell a eukaryote or prokaryote? How do you know?
4. Keeping in mind that the mouth is the first site of chemical digestion in a human. Your saliva starts the process of breaking down the food you eat. Keeping this in mind, what organelle do you think would be numerous inside the cells of your mouth? Explain.
Procedure:
A. Wet Mount of an Onion Cell
Sketch the cell at low and high power. Label the nucleus, cytoplasm, and cell wall of a single cell. Draw your cells to scale.
B. Wet Mount of an Elodea Leaf Cell
Sketch the cell at low and high power. Label the chloroplasts, cytoplasm, and cell wall of a single cell. The nucleus may be visible as well—it will be a large, clear figure. Draw your cells to scale.
Questions:
1. Describe the shape and the location of chloroplasts.
2. Were chloroplasts observed in the onion cells? Why or why not?
3. “Animal cells have mitochondria; plant cells have chloroplasts.” Is this statement true or false? Explain.
4. Fill out the Venn diagram below to show the differences and similarities between the onion cells and the Elodea cells.


15.3: Reading- Changes in Promotion
Local languages, colors, and religious beliefs all impact how global marketers promote their products and services in different countries.
KEY TAKEAWAY
- To successfully implement global marketing strategies, brands must ensure their promotional campaigns take into account how consumer behavior is shaped by internal conditions and external influences.
- Global companies must be nimble enough to adapt changing local market trends, tastes, and needs to their promotional mix.
- When launching global advertising, public relations or sales campaigns, global companies test promotion ideas to provide results that are comparable across countries.
- Using measures can be particularly helpful for marketers since they are based on visual, not verbal, elements of the promotion.
Terms
- Measure : To ascertain the quantity of a unit of material via calculated comparison with respect to a standard.
- Demographics: The observable characteristics of a population, such as physical traits, economic traits, occupational traits, and more.
Changes in Promotion
Before a company decides to become global, it must consider a multitude of factors unique to the international marketing environment. These factors are social, cultural, political, legal, competitive, economic, and even technological in nature. Ultimately, at the global marketing level, a company trying to speak with one voice is faced with many challenges when creating a worldwide marketing plan. Unless a company holds the same position against its competition in all markets (market leader, low cost, etc.), it is impossible to launch identical marketing plans worldwide. Thus, global companies must be nimble enough to adapt to changing local market trends, tastes, and needs.
For global advertisers, there are four potentially competing business objectives that must be balanced when developing worldwide advertising: building a brand while speaking with one voice, developing economies of scale in the creative process, maximizing local effectiveness of advertisements, and increasing the company’s speed of implementation. Global marketers can use the following approaches when executing global promotional programs: exporting executions, producing local executions, and importing ideas that travel.
Factors in Global Promotion
To successfully implement these approaches, brands must ensure their promotional campaigns take into how consumer behavior is shaped by internal conditions (e.g., demographics, knowledge, attitude, beliefs) and external influences (e.g., culture, ethnicity, family, lifestyle) in local markets.
- Language – The importance of language differences is extremely crucial in global marketing, as there are almost 3,000 languages in the world. Language differences have caused many problems for marketers in designing advertising campaigns and product labels. Language becomes even more significant if a country’s population speaks several languages.
- Colors – Colors also have different meanings in different cultures. For example, in Egypt, the country’s national color of green is considered unacceptable for packaging because religious leaders once wore it. In Japan, black and white are colors of mourning and should not be used on a product’s package. Similarly, purple is unacceptable in Hispanic nations because it is associated with death.
- Values – An individual’s values arise from his or her moral or religious beliefs and are learned through experiences. For example, Americans place a very high value on material well-being and are much more likely to purchase status symbols than people in India. In India, the Hindu religion forbids the consumption of beef.
- Business norms – The norms of conducting business also vary from one country to the next. For example, in France, wholesalers do not like to promote products. They are mainly interested in supplying retailers with the products they need.
- Religious beliefs – A person’s religious beliefs can affect shopping patterns and products purchased in addition to his or her values. In the United States and other Christian nations, Christmas time tends to be a major sales period. In other religions, significant religious holidays may or may not serve as popular times for purchasing products.
There are many other factors, including a country’s political or legal environment, monetary circumstances, and technological environment that can impact a brand’s promotional mix. Companies have to be ready to quickly respond and adapt to these challenges as they evolve and fluctuate in the market of each country.
Changing the Global Promotional Mix
When launching global advertising, public relations or sales campaigns, global companies test promotional ideas using marketing research systems that provide results comparable across countries. The ability to identify the elements or moments of an advertisement that contribute to the success of a product launch or expansion is how economies of scale are maximized in marketing communications. Market research measures such as flow of attention, flow of emotion, and branding moments provide insight into what is working in an advertisement in one or many countries. These measures can be particularly helpful for marketers since they are based on visual, not verbal, elements of the promotion.
Considering these measures along with conducting extensive market research is essential to determining the success of promotional tactics in any country or region. Once brands discover what works (and what does not) in their promotional mix, those ideas can be imported by any other market. Likewise, companies can use this intelligence to modify various elements in their promotional mix that are receiving minimal or unfavorable response from global audiences.
GLOSSARY
Advertisement
A commercial solicitation designed to sell some commodity or service.
Advertising
Communication for the purpose of influencing potential customers about products and services. A form of communication for marketing and used to encourage or persuade an audience (viewers, readers or listeners; sometimes a specific group) to continue or take some new action.
Attitude
A positive or negative evaluation of people, objects, events, or ideas in one’s environment an expression of favor or disfavor toward a person, place, thing, or event (the attitude object). Prominent psychologist Gordon Allport once described attitude as, “the most distinctive and indispensable concept in contemporary social psychology.” Disposition or state of mind.
Belief
Mental acceptance of a claim as truth regardless of supporting or contrary empirical evidence.
Brand
A name, symbol, logo, or other item used to distinguish a product, service, or its provider. The reputation of an organization, a product, or a person among some segment of the population.
Branding
This process involves researching, developing, and implementing brand names, brand marks, trade characters, and trademarks. A business’s ability to communicate a specific image, generally one that will entice consumers.
Consumer
Someone who acquires goods or services for direct use or ownership rather than for resale or use in production and manufacturing. The consumer is the one who pays to consume the goods and services produced. As such, consumers play a vital role in the economic system of a nation. In the absence of their effective demand, the producers would lack a key motivation to produce, which is to sell to consumers.
Consumer Behavior
The study of individuals, groups, or organizations and the processes they use to select, secure, and dispose of products, services, experiences, or ideas to satisfy needs; and the impacts that these processes have on the consumer and society.
Communication
The concept or state of exchanging information between entities. an instance of information transfer; a conversation or discourse the concept or state of exchanging data or information between entities.
Culture
The beliefs, values, behavior and material objects that constitute a people’s way of life; the arts, customs, and habits that characterize a particular society or nation. The sum of learned beliefs, values, and customs that regulate the behavior of members of a particular society. The arts, customs, and habits that characterize a particular society or nation. The language and peculiarities of a geographical location. A culture is the combination of the language that you speak and the geographical location you belong to. The distinct ways that people living in different parts of the world classified and represented their experiences.
Demographic
A characteristic used to identify people within a statistical framework. A demographic criterion: a characteristic used to classify people for statistical purposes, such as age, race, or gender. A characteristic used to classify people for statistical purposes, such as age, race, or gender. A grouping of people for statistical purposes, based as age, race, gender, etc.
Economies of scale
A process where an increase in quantity will result in a decrease of average cost of production (per unit). The characteristics of a production process in which an increase in the scale of the firm causes a decrease in the long run, average cost of each unit. The cost advantages that an enterprise obtains due to expansion. As the scale of output is increased, factors such as facility size and usage levels of inputs cause the producer’s average cost per unit to fall. The characteristics of a production process in which an increase in the scale of the firm causes a decrease in the long run average cost of each unit.
Global marketing
Global marketing is marketing on a worldwide scale, reconciling or taking commercial advantage of global operational differences, similarities and opportunities in order to meet global objectives.
Market
A group of potential customers for one’s product. One of the many varieties of systems, institutions, procedures, social relations and infrastructures whereby parties engage in exchange.
Marketing
The process of communicating the value of a product or service to customers. The promotion, distribution and selling of a product or service; includes market research and advertising.
Marketing environment
The factors and forces that affect a firm’s ability to build and maintain successful relationships with customers.
Market research (also called marketing research)
The function that links the consumers, customers, and public to the marketer through information. This information is used to identify and define marketing opportunities and problems; generate, refine, and evaluate marketing actions; monitor marketing performance; and improve understanding of marketing as a process. The systematic collection and evaluation of data regarding customers’ preferences for actual and potential products and services.
Marketing strategy
A process that can allow an organization to concentrate its resources on the optimal opportunities with the goals of increasing sales and achieving a sustainable competitive advantage
Process
A series of events to produce a result, especially as contrasted to product. in reference to capabilities, a process is how the capability is executed.
Product
Any tangible or intangible good or service that is a result of a process and that is intended for delivery to a customer or end user. Anything, either tangible or intangible, offered by the firm as a solution to the needs and wants of the consumer; something that is profitable or potentially profitable; goods or a service that meets the requirements of the various governing offices or society.
Promotion
The advancement of an employee’s rank or position in an organizational hierarchy system.Promotion represents all of the methods of communication that a marketer may use to provide information to different parties about the product. Promotion comprises elements such as: advertising, public relations, personal selling and sales promotion. dissemination of information about a product, product line, brand, or company.
Public
People. Includes people who look, think, and act the same as well as those who do not.
Public relations (PR)
The practice of managing the flow of information between an individual or an organization and the public.
Retailer
One who purchases goods or products in large quantities from manufacturers directly or through a wholesale, and then sells smaller quantities to the consumer for a profit.
Service
Action or work that is produced, then traded, bought or sold, and then finally consumed.
Strategy
A plan of action intended to accomplish a specific goal.
Tactics
The achievement of objectives through strategy.
Trend
An inclination in a particular direction the long-term movement in time series data after other components have been accounted for.
Value
The degree of importance given to something.  A customer’s perception of relative price (the cost to own and use) and performance (quality).
Wholesaler
A person or company that sells goods wholesale is a middleman that buys its merchandise from a third party supplier and resells the merchandise to retail businesses or the end consumer. A wholesaler normally does not sell to other wholesalers.
- Boundless Business. Authored by : Boundless. Provided by : Boundless. Located at : https://www.boundless.com/business/ . License : CC BY-SA: Attribution-ShareAlike
- Image of Potato Chips. Authored by : kevin dooley. Located at : https://www.flickr.com/photos/pagedooley/6158689227/sizes/l/ . License : CC BY: Attribution


9.10: Introduction to Organizational Culture
What you’ll learn to do: describe organizational culture, and explain how culture can be a competitive advantage
Organizational culture is a term that describes the shared values and goals of an organization. When everyone in a corporation shares the same values and goals, it’s possible to create a culture of mutual respect, collaboration, and support. Companies that have a strong, supportive culture are more likely to attract highly qualified, loyal employees who understand and work toward the company’s best interests.
Contributors and Attributions
CC licensed content, Original
- Introduction to Organizational Culture. Authored by : Lisa Jo Rudy and Lumen Learning. License : CC BY: Attribution


6.5: Exercise - A Basic Assignment of Events to Bins
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Enough theory—let’s make some bins! If EEGLAB is already running, I recommend quitting it and restarting it to make sure everything is fresh. Set Chapter_6 to be Matlab’s current folder. Load the dataset named 12_P3_corrected_elist.set (using EEGLAB > File > Load existing dataset ). Scroll through the EEG (using EEGLAB > Plot > Channel data (scroll) ) and familiarize yourself with it. For example, take a look at the sequence of event codes and match them with the codes in Table 6.1. When I load a dataset or ERPset, I don’t do anything until I’ve looked at the waveforms. Many times, this visual inspection has made me realize that I have the wrong data or that there is something about the data that is incompatible with what I was planning to do next.
Do you see any eyeblinks in the VEOG-lower or FP1 channels? Did you need to remove the DC offset to see all the channels? The answer is “no” for both questions. This gives you some clues about the preprocessing steps that have already been applied to this dataset. What operations do you think have already been applied?
To keep the exercises in this chapter simple, the waveforms have had an artifact correction procedure applied. Instead of excluding epochs that contain blinks and eye movements, the voltages for the blinks and eye movements have been estimated and subtracted from the waveforms. That way, we won’t need to throw out any trials in the exercises in this chapter. This is why the filename for the dataset has _corrected in it. A high-pass filter (half amplitude cutoff at 0.1 Hz) has also been applied to remove slow drifts, and the EventList was added.
We’re finally read to assign the events to bins. Select EEGLAB > ERPLAB > Assign bins (BINLISTER) , and set it up like Screenshot 6.1. Specifically, use the Browse button near the top to select the bin descriptor file ( BDF_P3.txt ). We want to read the EventList from the current dataset, and we want to write the updated version with the bin information to the current dataset. We also want to write it to a text file, so check the Text file box and put elist_bins.txt in the corresponding text box. Click RUN , and then name the new dataset 12_P3_corrected_elist_bins .
You should see the text file with the EventList in it ( elist_bins.txt ) in Matlab’s Current Folder pane. Double-click on it to open it the text editor. Near the top, just under the head information, you should see this:
bin 1, # 30, Rare, Correct
bin 2, # 153, Frequent, Correct
This tells you that 30 events were found that match the bin descriptor for Bin 1, and 153 were found that match the bin descriptor for Bin 2. How many should we have had? This is an extremely important question to answer, because errors in event codes and in assigning events to bins are quite common, and many of these errors will lead to the wrong number of trials per bin. In the task description in the beginning of the chapter, you learned that there were 5 equiprobable letters, 5 blocks of trials (one with each letter as the target), and 40 trials per block. This gives us 200 total trials. Given that 1 of the 5 letters was the target in each block, target probability was 20%. This means that we should have had 40 targets and 160 nontargets over the course of a session. Why, then, do we only have 30 instances of Bin 1 and 153 instances of Bin 2?
The answer is that Bins 1 and 2 are limited to trials with correct responses and an RT of 200-1000 ms. So, we can’t use these numbers to verify that we have the correct number of event codes. As described in Chapter 2, another way that we can verify the number of event codes is to use EEGLAB > ERPLAB > EventList > Summarize current EEG event codes . Give that a try.
The resulting list should print in the Matlab Command Window, but it still isn’t very informative. First, we have a ton of different event codes. Second, when we created the randomized sequences of events in our stimulus presentation script, we specified a certain probability of each letter but not a certain number . That is, we guaranteed that there were 8 instances of the letter A when A was the target, but the other 32 stimuli in this block were sampled completely at random from the other 4 letters. So, you can verify that we had eight targets in each block, but it’s not immediately obvious that we had the right number of nontargets.
To verify that we had the right number of Rare and Frequent stimuli, make a copy of BDF_P3.txt , and edit this copy so that the event descriptors don’t require a correct response. Then run BINLISTER again (on 12_P3_corrected_elist ) but choose a new filename for the text file that will contain the new EventList. When you look at this new EventList, you should see 40 trials in Bin 1 and 160 trials in Bin 2.
Now go back to the text file with the first EventList ( elist_bins.txt ). Every event code is listed, with the bin assignment in the bin column at the far right. Note that the bin field is empty for the response event codes, because these event codes are not used as time-locking events in this analysis. For the stimulus event codes, you should find a 1 or 2 in this field, indicating whether the stimulus was the target letter or one of the nontarget letters. However, the bin field is empty for some of the stimulus event codes. These are error trials. We’ll take a closer look at the errors in a later exercise.


18.3: Learning the Basics, and Learning Them in R
Okay, that was… long. And even that listing is massively incomplete. There really are a lot of big ideas in statistics that I haven’t covered in this book. It can seem pretty depressing to finish a 600-page textbook only to be told that this only the beginning, especially when you start to suspect that half of the stuff you’ve been taught is wrong. For instance, there are a lot of people in the field who would strongly argue against the use of the classical ANOVA model, yet I’ve devote two whole chapters to it! Standard ANOVA can be attacked from a Bayesian perspective, or from a robust statistics perspective, or even from a “it’s just plain wrong” perspective (people very frequently use ANOVA when they should actually be using mixed models). So why learn it at all?
As I see it, there are two key arguments. Firstly, there’s the pure pragmatism argument. Rightly or wrongly, ANOVA is widely used. If you want to understand the scientific literature, you need to understand ANOVA. And secondly, there’s the “incremental knowledge” argument. In the same way that it was handy to have seen one-way ANOVA before trying to learn factorial ANOVA, understanding ANOVA is helpful for understanding more advanced tools, because a lot of those tools extend on or modify the basic ANOVA setup in some way. For instance, although mixed models are way more useful than ANOVA and regression, I’ve never heard of anyone learning how mixed models work without first having worked through ANOVA and regression. You have to learn to crawl before you can climb a mountain.
Actually, I want to push this point a bit further. One thing that I’ve done a lot of in this book is talk about fundamentals. I spent a lot of time on probability theory. I talked about the theory of estimation and hypothesis tests in more detail than I needed to. When talking about R, I spent a lot of time talking about how the language works, and talking about things like writing your own scripts, functions and programs. I didn’t just teach you how to draw a histogram using
hist()
, I tried to give a basic overview of how the graphics system works. Why did I do all this? Looking back, you might ask whether I really
needed
to spend all that time talking about what a probability distribution is, or why there was even a section on probability density. If the goal of the book was to teach you how to run a t-test or an ANOVA, was all that really necessary? Or, come to think of it, why bother with R at all? There are lots of free alternatives out there: PSPP, for instance, is an SPSS-like clone that is totally free, has simple “point and click” menus, and can (I think) do every single analysis that I’ve talked about in this book. And you can learn PSPP in about 5 minutes. Was this all just a huge waste of everyone’s time???
The answer, I hope you’ll agree, is no. The goal of an introductory stats is
not
to teach ANOVA. It’s not to teach t-tests, or regressions, or histograms, or p-values. The goal is to start you on the path towards becoming a skilled data analyst. And in order for you to become a skilled data analyst, you need to be able to do more than ANOVA, more than t-tests, regressions and histograms. You need to be able to
think properly
about data. You need to be able to learn the more advanced statistical models that I talked about in the last section, and to understand the theory upon which they are based. And you need to have access to software that will let you use those advanced tools. And this is where – in my opinion at least – all that extra time I’ve spent on the fundamentals pays off. If you understand the graphics system in R, then you can draw the plots that
you
want, not just the canned plots that someone else has built into R for you. If you understand probability theory, you’ll find it much easier to switch from frequentist analyses to Bayesian ones. If you understand the core mechanics of R, you’ll find it much easier to generalise from linear regressions using
lm()
to using generalised linear models with
glm()
or linear mixed effects models using
lme()
and
lmer()
. You’ll even find that a basic knowledge of R will go a long way towards teaching you how to use other statistical programming languages that are based on it. Bayesians frequently rely on tools like WinBUGS and JAGS, which have a number of similarities to R, and can in fact be called from within R. In fact, because R is the “lingua franca of statistics”, what you’ll find is that most ideas in the statistics literature has been implemented somewhere as a package that you can download from CRAN. The same cannot be said for PSPP, or even SPSS.
In short, I think that the big payoff for learning statistics this way is extensibility . For a book that only covers the very basics of data analysis, this book has a massive overhead in terms of learning R, probability theory and so on. There’s a whole lot of other things that it pushes you to learn besides the specific analyses that the book covers. So if your goal had been to learn how to run an ANOVA in the minimum possible time, well, this book wasn’t a good choice. But as I say, I don’t think that is your goal. I think you want to learn how to do data analysis. And if that really is your goal, you want to make sure that the skills you learn in your introductory stats class are naturally and cleanly extensible to the more complicated models that you need in real world data analysis. You want to make sure that you learn to use the same tools that real data analysts use, so that you can learn to do what they do. And so yeah, okay, you’re a beginner right now (or you were when you started this book), but that doesn’t mean you should be given a dumbed-down story, a story in which I don’t tell you about probability density, or a story where I don’t tell you about the nightmare that is factorial ANOVA with unbalanced designs. And it doesn’t mean that you should be given baby toys instead of proper data analysis tools. Beginners aren’t dumb; they just lack knowledge. What you need is not to have the complexities of real world data analysis hidden from from you. What you need are the skills and tools that will let you handle those complexities when they inevitably ambush you in the real world.
And what I hope is that this book – or the finished book that this will one day turn into – is able to help you with that.
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9.15: Comets in History
Comets have often been written about and portrayed in history. Some of the earliest comet observations were recorded by the Chinese on oracle bones. Oracle bones were pieces of turtle shells and bones used for a form of divination. Aristotle thought and proposed that comets were an atmospheric phenomena, in other words, not in our solar system or in space.
Comets were considered bad omens until the 16th century. These omens would include crop failures, diseases, deaths of royalty, or other such catastrophic events. Pliny the Elder (23-79 AD), a Roman natural philosopher, thought comets were the cause of political issues and death. Halley’s Comet made a passage at the same time during the Battle of Hastings in 1066.


3.7: Exceptions to the Octet Rule
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Learning Objectives
- To assign a Lewis dot symbol to elements not having an octet of electrons in their compounds.
Three cases can be constructed that do not follow the octet rule, and as such, they are known as the exceptions to the octet rule. Following the Octet Rule for Lewis Dot Structures leads to the most accurate depictions of stable molecular and atomic structures and because of this we always want to use the octet rule when drawing Lewis Dot Structures. However, it is hard to imagine that one rule could be followed by all molecules. There is always an exception, and in this case, three exceptions:
- When there are an odd number of valence electrons
- When there are too few valence electrons
- When there are too many valence electrons
Exception 1: Species with Odd Numbers of Electrons
The first exception to the Octet Rule is when there are an odd number of valence electrons. An example of this would be Nitrogen (II) Oxide also called nitric oxide (\(\ce{NO}\). Nitrogen has 5 valence electrons while Oxygen has 6. The total would be 11 valence electrons to be used. The Octet Rule for this molecule is fulfilled in the above example, however that is with 10 valence electrons. The last one does not know where to go. The lone electron is called an unpaired electron. But where should the unpaired electron go? The unpaired electron is usually placed in the Lewis Dot Structure so that each element in the structure will have the lowest formal charge possible. The formal charge is the perceived charge on an individual atom in a molecule when atoms do not contribute equal numbers of electrons to the bonds they participate in .
No formal charge at all is the most ideal situation. An example of a stable molecule with an odd number of valence electrons would be nitric oxide. nitric oxide has 11 valence electrons. If you need more information about formal charges, see Lewis Structures. If we were to imagine nitric oxide had ten valence electrons we would come up with the Lewis Structure (Figure \(\PageIndex{1}\)):
Let's look at the formal charges of Figure \(\PageIndex{2}\) based on this Lewis structure. Nitrogen normally has five valence electrons. In Figure \(\PageIndex{1}\), it has two lone pair electrons and it participates in two bonds (a double bond) with oxygen. This results in nitrogen having a formal charge of +1. Oxygen normally has six valence electrons. In Figure \(\PageIndex{1}\), oxygen has four lone pair electrons and it participates in two bonds with nitrogen. Oxygen therefore has a formal charge of 0. The overall molecule here has a formal charge of +1 (+1 for nitrogen, 0 for oxygen. +1 + 0 = +1). However, if we add the eleventh electron to nitrogen (because we want the molecule to have the lowest total formal charge), it will bring both the nitrogen and the molecule's overall charges to zero, the most ideal formal charge situation. That is exactly what is done to get the correct Lewis structure for nitric oxide (Figure \(\PageIndex{2}\)):
Free Radicals
There are actually very few stable molecules with odd numbers of electrons that exist, since that unpaired electron is willing to react with other unpaired electrons. Most odd electron species are highly reactive, which we call Free Radicals. Because of their instability, free radicals bond to atoms in which they can take an electron from in order to become stable, making them very chemically reactive. Radicals are found as both reactants and products, but generally react to form more stable molecules as soon as they can. In order to emphasize the existence of the unpaired electron, radicals are denoted with a dot in front of their chemical symbol as with \(\cdot OH\), the hydroxyl radical. An example of a radical you may by familiar with already is the gaseous chlorine atom, denoted \(\cdot Cl\). Interestingly, an odd Number of Valence Electrons will result in the molecule being paramagnetic.
Exception 2: Incomplete Octets
The second exception to the Octet Rule is when there are too few valence electrons that results in an incomplete Octet. There are even more occasions where the octet rule does not give the most correct depiction of a molecule or ion. This is also the case with incomplete octets. Species with incomplete octets are pretty rare and generally are only found in some beryllium, aluminum, and boron compounds including the boron hydrides. Let's take a look at one such hydride, BH 3 (Borane).
If one were to make a Lewis structure for BH 3 following the basic strategies for drawing Lewis structures, one would probably come up with this structure (Figure \(\PageIndex{2}\)):
The problem with this structure is that boron has an incomplete octet; it only has six electrons around it. Hydrogen atoms can naturally only have only 2 electrons in their outermost shell (their version of an octet), and as such there are no spare electrons to form a double bond with boron. One might surmise that the failure of this structure to form complete octets must mean that this bond should be ionic instead of covalent. However, boron has an electronegativity that is very similar to hydrogen, meaning there is likely very little ionic character in the hydrogen to boron bonds, and as such this Lewis structure, though it does not fulfill the octet rule, is likely the best structure possible for depicting BH 3 with Lewis theory. One of the things that may account for BH 3 's incomplete octet is that it is commonly a transitory species, formed temporarily in reactions that involve multiple steps.
Let's take a look at another incomplete octet situation dealing with boron, BF 3 (Boron trifluorine). Like with BH 3 , the initial drawing of a Lewis structure of BF 3 will form a structure where boron has only six electrons around it (Figure \(\PageIndex{4}\)).
If you look Figure \(\PageIndex{4}\), you can see that the fluorine atoms possess extra lone pairs that they can use to make additional bonds with boron, and you might think that all you have to do is make one lone pair into a bond and the structure will be correct. If we add one double bond between boron and one of the fluorines we get the following Lewis Structure (Figure \(\PageIndex{5}\)):
Each fluorine has eight electrons, and the boron atom has eight as well! Each atom has a perfect octet, right? Not so fast. We must examine the formal charges of this structure. The fluorine that shares a double bond with boron has six electrons around it (four from its two lone pairs of electrons and one each from its two bonds with boron). This is one less electron than the number of valence electrons it would have naturally (Group Seven elements have seven valence electrons), so it has a formal charge of +1. The two flourines that share single bonds with boron have seven electrons around them (six from their three lone pairs and one from their single bonds with boron). This is the same amount as the number of valence electrons they would have on their own, so they both have a formal charge of zero. Finally, boron has four electrons around it (one from each of its four bonds shared with fluorine). This is one more electron than the number of valence electrons that boron would have on its own, and as such boron has a formal charge of -1.
This structure is supported by the fact that the experimentally determined bond length of the boron to fluorine bonds in BF 3 is less than what would be typical for a single bond (see Bond Order and Lengths). However, this structure contradicts one of the major rules of formal charges: Negative formal charges are supposed to be found on the more electronegative atom(s) in a bond, but in the structure depicted in Figure \(\PageIndex{5}\), a positive formal charge is found on fluorine, which not only is the most electronegative element in the structure, but the most electronegative element in the entire periodic table (\(\chi=4.0\)). Boron on the other hand, with the much lower electronegativity of 2.0, has the negative formal charge in this structure. This formal charge-electronegativity disagreement makes this double-bonded structure impossible.
However the large electronegativity difference here, as opposed to in BH 3 , signifies significant polar bonds between boron and fluorine, which means there is a high ionic character to this molecule. This suggests the possibility of a semi-ionic structure such as seen in Figure \(\PageIndex{6}\):
None of these three structures is the "correct" structure in this instance. The most "correct" structure is most likely a resonance of all three structures: the one with the incomplete octet (Figure \(\PageIndex{4}\)), the one with the double bond (Figure \(\PageIndex{5}\)), and the one with the ionic bond (Figure \(\PageIndex{6}\)). The most contributing structure is probably the incomplete octet structure (due to Figure \(\PageIndex{5}\) being basically impossible and Figure \(\PageIndex{6}\) not matching up with the behavior and properties of BF 3 ). As you can see even when other possibilities exist, incomplete octets may best portray a molecular structure.
As a side note, it is important to note that BF 3 frequently bonds with a F - ion in order to form BF 4 - rather than staying as BF 3 . This structure completes boron's octet and it is more common in nature. This exemplifies the fact that incomplete octets are rare, and other configurations are typically more favorable, including bonding with additional ions as in the case of BF 3 .
Example \(\PageIndex{1}\): \(NF_3\)
Draw the Lewis structure for boron trifluoride (BF 3 ).
Solution
1. Add electrons (3*7) + 3 = 24
2. Draw connectivities:
3. Add octets to outer atoms:
4. Add extra electrons (24-24=0) to central atom:
5. Does central electron have octet?
- NO. It has 6 electrons
- Add a multiple bond (double bond) to see if central atom can achieve an octet:
6. The central Boron now has an octet (there would be three resonance Lewis structures)
However...
- In this structure with a double bond the fluorine atom is sharing extra electrons with the boron.
- The fluorine would have a '+' partial charge, and the boron a '-' partial charge, this is inconsistent with the electronegativities of fluorine and boron.
- Thus, the structure of BF 3 , with single bonds, and 6 valence electrons around the central boron is the most likely structure
BF 3 reacts strongly with compounds which have an unshared pair of electrons which can be used to form a bond with the boron:
Exception 3: Expanded Valence Shells
More common than incomplete octets are expanded octets where the central atom in a Lewis structure has more than eight electrons in its valence shell. In expanded octets, the central atom can have ten electrons, or even twelve. Molecules with expanded octets involve highly electronegative terminal atoms, and a nonmetal central atom found in the third period or below , which those terminal atoms bond to. For example, \(PCl_5\) is a legitimate compound (whereas \(NCl_5\)) is not:
Expanded valence shells are observed only for elements in period 3 (i.e. n=3) and beyond
The 'octet' rule is based upon available n s and n p orbitals for valence electrons (2 electrons in the s orbitals, and 6 in the p orbitals). Beginning with the n=3 principle quantum number, the d orbitals become available ( l =2). The orbital diagram for the valence shell of phosphorous is:
Hence, the third period elements occasionally exceed the octet rule by using their empty d orbitals to accommodate additional electrons. Size is also an important consideration:
- The larger the central atom, the larger the number of electrons which can surround it
- Expanded valence shells occur most often when the central atom is bonded to small electronegative atoms, such as F, Cl and O.
There is currently much scientific exploration and inquiry into the reason why expanded valence shells are found. The top area of interest is figuring out where the extra pair(s) of electrons are found. Many chemists think that there is not a very large energy difference between the 3p and 3d orbitals, and as such it is plausible for extra electrons to easily fill the 3d orbital when an expanded octet is more favorable than having a complete octet. This matter is still under hot debate, however and there is even debate as to what makes an expanded octet more favorable than a configuration that follows the octet rule.
One of the situations where expanded octet structures are treated as more favorable than Lewis structures that follow the octet rule is when the formal charges in the expanded octet structure are smaller than in a structure that adheres to the octet rule, or when there are less formal charges in the expanded octet than in the structure a structure that adheres to the octet rule.
Example \(\PageIndex{2}\): The \(SO_4^{-2}\) ion
Such is the case for the sulfate ion, SO 4 -2 . A strict adherence to the octet rule forms the following Lewis structure:
If we look at the formal charges on this molecule, we can see that all of the oxygen atoms have seven electrons around them (six from the three lone pairs and one from the bond with sulfur). This is one more electron than the number of valence electrons then they would have normally, and as such each of the oxygens in this structure has a formal charge of -1. Sulfur has four electrons around it in this structure (one from each of its four bonds) which is two electrons more than the number of valence electrons it would have normally, and as such it carries a formal charge of +2.
If instead we made a structure for the sulfate ion with an expanded octet, it would look like this:
Looking at the formal charges for this structure, the sulfur ion has six electrons around it (one from each of its bonds). This is the same amount as the number of valence electrons it would have naturally. This leaves sulfur with a formal charge of zero. The two oxygens that have double bonds to sulfur have six electrons each around them (four from the two lone pairs and one each from the two bonds with sulfur). This is the same amount of electrons as the number of valence electrons that oxygen atoms have on their own, and as such both of these oxygen atoms have a formal charge of zero. The two oxygens with the single bonds to sulfur have seven electrons around them in this structure (six from the three lone pairs and one from the bond to sulfur). That is one electron more than the number of valence electrons that oxygen would have on its own, and as such those two oxygens carry a formal charge of -1. Remember that with formal charges, the goal is to keep the formal charges (or the difference between the formal charges of each atom) as small as possible. The number of and values of the formal charges on this structure (-1 and 0 (difference of 1) in Figure \(\PageIndex{12}\), as opposed to +2 and -1 (difference of 3) in Figure \(\PageIndex{12}\)) is significantly lower than on the structure that follows the octet rule, and as such an expanded octet is plausible, and even preferred to a normal octet, in this case.
Example \(\PageIndex{3}\): The \(ICl_4^-\) Ion
Draw the Lewis structure for \(ICl_4^-\) ion.
Solution
1. Count up the valence electrons: 7+(4*7)+1 = 36 electrons
2. Draw the connectivities:
3. Add octet of electrons to outer atoms:
4. Add extra electrons (36-32= 4 ) to central atom:
5. The ICl 4 - ion thus has 12 valence electrons around the central Iodine (in the 5 d orbitals)
Expanded Lewis structures are also plausible depictions of molecules when experimentally determined bond lengths suggest partial double bond characters even when single bonds would already fully fill the octet of the central atom. Despite the cases for expanded octets, as mentioned for incomplete octets, it is important to keep in mind that, in general, the octet rule applies.
Summary
Following the Octet Rule for Lewis Dot Structures leads to the most accurate depictions of stable molecular and atomic structures and because of this we always want to use the octet rule when drawing Lewis Dot Structures. There are three exceptions: (1) When there are an odd number of valence electrons, (2) When there are too few valence electrons, and (3) when there are too many valence electrons
References
- Petrucci, Ralph H.; Harwood, William S.; Herring, F. G.; Madura, Jeffrey D. General Chemistry: Principles & Modern Applications . 9th Ed. New Jersey. Pearson Education, Inc. 2007.
- Moore, John W.; Stanitski, Conrad L. ; Jurs, Peter C. Chemistry; The Molecular Science . 2nd Ed. 2004.


11.11: Why It Matters- Pricing Strategies
Why use pricing strategies to enhance marketing of products and services?
When Amazon.com was created in 1994, the company sold books online. While many viewed it as a real threat to traditional bookstores, few, other than its founder and CEO, Jeff Bezos, imagined what the company would become. Today the services that Amazon offers are extensive, and many of them center on a quiet service membership called Amazon Prime. The following video shows the impact of this offering on one American family.
You can view the transcript for “Amazon Prime” (opens in new window) .
What is Amazon Prime? When Amazon launched the product in 2005, it included free two-day shipping for most orders, and it was priced as an annual $79 membership fee. At the time, analysts wondered how Amazon could justify the value to customers (implying that it was too expensive) and, at the same time, how it could afford to keep offering the service if demand should grow (implying that it was too cheap to cover costs).
Greg Greeley, the vice president of Amazon Prime Global, reflected on the company’s decision and told the Washington Post,
We have always thought of it as the best bargain in shopping—Jeff [Bezos] went on record again saying that—in 2005 when we launched it with unlimited two-day shipping on 1 million items. But we did not think of it as a shipping program, but as a convenience program.
Prime introduced three concepts. It had two-day shipping at a time when people expected to pay for shipping and still not get their items for four to seven business days. It was very predictable: We put it on the Web site that if you ordered in the next 3 hours and 20 min., for example, you could have it in two days. And it was an unlimited, single membership fee that made fast delivery an everyday experience instead of an occasional indulgence. [1]
Was the initial $79 price too low? Too high? Does it really matter that much?
After 2005, Amazon began adding services to the Prime membership without raising the price. Today the service includes unlimited video streaming, unlimited music streaming, $5.99 flat-fee shipping on discounted household items, access to a Kindle lending library and a host of others services. In spite of increased services, Amazon held pricing flat at $79 per year. In 2013, Amazon admitted that by simply adjusting the 2005 price for inflation, transportation, and fuel costs, the price would be more than $100 today.
Finally, in January 2014 Amazon told its customers to expect a price increase of $40 for Amazon Prime memberships, which would make the new price $119. In March 2014, the company announced the actual price increase: a $20 increase, or annual price of $99. While there were some disgruntled customers, the majority accepted the increase without complaint.
While Amazon doesn’t share its usage or financial data for Amazon Prime, analysts have completed customer surveys, analyzed Internet traffic, and reviewed enough detailed financial data to support the following:
- Amazon loses at least $1 billion annually on Prime-related shipping expenses
- Amazon spent $1.3 billion into Prime Instant Video in 2014, over and above the shipping costs
- Amazon Prime has between 40 and 50 million subscribers
- Prime members spend an average of $538 annually with Amazon, far more than the $320 by non-Prime members [2]
Is it strategic genius or terrible folly for Amazon to lose billions of dollars a year on Amazon Prime on account of its pricing? Is Amazon actually losing money on Prime, or is Prime bringing in enough other sales to cover its costs . . . and more?
Choosing a price is as easy as picking a random number. As you’ll discover in this module, however, finding the right price to achieve company objectives and provide sustained value to customers is much more complicated.
Learning Outcomes
- Discuss how price affects the value of the organization’s products or services
- Explain the primary factors to consider in pricing
- Compare common pricing strategies
- Explain price elasticity and how it can be used to set price
- Explain the use of competitive bidding for B2B pricing
- www.washingtonpost.com/news/the-switch/wp/2015/02/03/what-amazons-learned-from-a-decade-of-prime/ ↵
- http://fortune.com/2015/02/03/inside-amazon-prime/ ↵
Contributors and Attributions
- Why It Matters: Pricing Strategies. Provided by : Lumen Learning. License : CC BY: Attribution
- Amazon Prime. Provided by : BBC. Located at : https://youtu.be/bh5nT_dqN4Q . License : CC BY-NC-ND: Attribution-NonCommercial-NoDerivatives


11.7: Why It Matters- Relevant Revenues and Costs
Why learn to determine relevant revenues and costs?
Knowing which costs are important and which we can ignore when making decisions will save time in the decision making process and also make it more effective. Some costs don’t make a difference, but unfortunately, there is no clear guide for which ones matter and which ones don’t.
Only with experience and practice, can a manager learn which costs are relevant to a decision. Learning the process is important for the profitability of your company and to make the best use of resources.
Sunk costs, opportunity costs and avoidable and unavoidable costs all need to be understood to determine what the differential costs are when you make decisions about adding or dropping a product line, making or buying a component part or figuring out how to best use a constrained resource.


7: Electronic Structure and Periodic Properties
The study of chemistry must at some point extend to the molecular level, for the physical and chemical properties of a substance are ultimately explained in terms of the structure and bonding of molecules. This module introduces some basic facts and principles that are needed for a discussion of organic molecules.
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- 7.1: Electromagnetic Energy
- Light and other forms of electromagnetic radiation move through a vacuum with a constant speed, c. This radiation shows wavelike behavior, which can be characterized by a frequency, ν, and a wavelength, λ, such that c = λν. Light is an example of a travelling wave. Other important wave phenomena include standing waves, periodic oscillations, and vibrations. Standing waves exhibit quantization, since their wavelengths are limited to discrete integer multiples of some characteristic lengths.
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- 7.2: The Bohr Model
- Bohr incorporated Planck’s and Einstein’s quantization ideas into a model of the hydrogen atom that resolved the paradox of atom stability and discrete spectra. The Bohr model of the hydrogen atom explains the connection between the quantization of photons and the quantized emission from atoms. Bohr described the hydrogen atom in terms of an electron moving in a circular orbit about a nucleus. He postulated that the electron was restricted to certain orbits characterized by discrete energies.
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- 7.3: Development of Quantum Theory
- Macroscopic objects act as particles. Microscopic objects (such as electrons) have properties of both a particle and a wave. but their exact trajectories cannot be determined. The quantum mechanical model of atoms describes the 3D position of the electron in a probabilistic manner according to a mathematical function called a wavefunction, often denoted as ψ. The squared magnitude of the wavefunction describes the distribution of the probability of finding the electron in a particular region in
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- 7.4: Electronic Structure of Atoms (Electron Configurations)
- The relative energy of the subshells determine the order in which atomic orbitals are filled. Electron configurations and orbital diagrams can be determined by applying the Pauli exclusion principle (no two electrons can have the same set of four quantum numbers) and Hund’s rule (whenever possible, electrons retain unpaired spins in degenerate orbitals). Electrons in the outermost orbitals, called valence electrons, are responsible for most of the chemical behavior of elements.
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- 7.5: Periodic Variations in Element Properties
- Electron configurations allow us to understand many periodic trends. Covalent radius increases as we move down a group because the n level (orbital size) increases. Covalent radius mostly decreases as we move left to right across a period because the effective nuclear charge experienced by the electrons increases, and the electrons are pulled in tighter to the nucleus. Anionic radii are larger than the parent atom, while cationic radii are smaller.
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- 7.E: Electronic Structure and Periodic Properties- Homework
- These are homework exercises to accompany the Textmap created for "Chemistry" by OpenStax. Complementary General Chemistry question banks can be found for other Textmaps and can be accessed here. In addition to these publicly available questions, access to private problems bank for use in exams and homework is available to faculty only on an individual basis; please contact Delmar Larsen for an account with access permission.
Contributors and Attributions
-
Paul Flowers (University of North Carolina - Pembroke), Klaus Theopold (University of Delaware) and Richard Langley (Stephen F. Austin State University) with contributing authors. Textbook content produced by OpenStax College is licensed under a Creative Commons Attribution License 4.0 license. Download for free at<EMAIL_ADDRESS>).


7.26.1: 7. 26B- Tracking Cells with Light
Advanced technology enables tracking cells with light by introducing fluorescent or luminescent reporter genes into the cells’ genome.
LEARNING OBJECTIVES
Compare the ways light can used to track cells
KEY TAKEAWAYS
Fluorescence and luminescence
Cells undergo many dynamic processes. In order to visualize these processes we need to be able to film cells over time. This can be achieved by using tools to monitor gene expression to track when proteins are made and where they go in the cell. In molecular biology, researchers use a reporter gene that they attach to a regulatory gene of interest. Reporter genes ideally have distinguishable properties that can be easily detected and measured. The most commonly used reporter genes have biofluorescent or bioluminescent characteristics and can be visualized with the aid of microscopy and other non-invasive imaging equipments. Examples of such reporters are the genes encoding for Green Fluorescent Protein (GFP) and luciferase, respectively. The discovery of GFP changed the way we look at cellular life today. GFP was first isolated from the jellyfish ( Aequorea victoria ) by the Japanese scientist Osuma Shimomura in the early 1960s. It was then cloned and its sequence identified in 1992 by Douglas Prasher. GFP is widely used in research laboratories as a marking tool to illuminate and track genes in fixed or living cells. Luciferase, isolated from fireflies, is an enzyme present in the cells of bioluminescent organisms that catalyzes the oxidation of luciferin and ATP producing light. Luciferase is similarly useful as a biological marker in living cells and organisms.
Transfection of reporter genes into cells
To introduce a reporter gene into an organism, scientists place the reporter gene and the gene of interest in the same DNA construct to be inserted into the cell or organism. For bacteria or prokaryotic cells in culture, this is usually in the form of a circular DNA molecule called a plasmid. It is important to use a reporter gene that is not natively expressed in the cell or organism under study, since the expression of the reporter is being used as a marker for successful uptake of the gene of interest. This gene’s regulatory sequence now controls the production of GFP or luciferase, in addition to the protein of interest. In cells where the gene is expressed, and the tagged proteins are produced, GFP or luciferase are produced at the same time. Thus, only those cells in which the tagged gene is expressed, or the target proteins are produced, will fluoresce when observed under fluorescence microscopy, or bioluminesce (emit light) when luciferin, the substrate for luciferase is added.
Application of GFP in molecular microbiology
GFP has many advantages over conventional reporter genes in that it is highly stable, non-toxic to living cells and organisms, detection tools are non-invasive and the green light is generated without the addition of external cofactors and measured without application of expensive equipment. Various applications of that reporter gene were documented and vary from being able to monitor microorganism ‘s survival in complex biological systems such as activated sludge to biodegradation of chemical compounds in soil. GFP allowed the detection, determination of spatial location and enumeration of bacterial cells from diverse environmental samples such as biofilm and water. GFP as biomarker is also useful in monitoring gene expression and protein localisation in bacterial cells.
Key Points
- The ability of tracking cells with light has revolutionized molecular biology and provided means to study biological processes as they happen.
- The most common tools used to illuminate a cell are fluorescent (GFP) and luminescent (luciferase) reporter genes.
- Reporter genes are introduced into the host ‘s genome and are controlled by the regulatory sequence of the gene under investigation (gene X). Thus when gene X is expressed it will drive along the expression of the reporter gene and the cell will fluoresce or emit light.
- Many laboratory devices are available to visualize illuminated living cells and these range from fluorescence microscopy to more advanced spectroscopy.
Key Terms
- Spectroscopy : use of light, sound or particle emission to study matter. The emissions provide information about the properties of the matter under investigation. The device often used for such analysis is a spectrometer, which records the spectrum of light emitted (or absorbed) by a given material.
- Fluorescence microscopy : optical microscope that uses fluorescence to study properties of substances. A sample is illuminated with light of a wavelength that excites fluorescence in the sample. The fluoresced light, which is usually at a longer wavelength than the illumination, is then imaged through a microscope objective.