Total 8,232. Note: In addition to its drugstores, Walgreens also operates home care facilities and specialty, institutional and mail service pharmacies. Its Take Care Health Systems subsidiary manages more than 400 convenient care clinics at Walgreens drugstores.
These different versions of hydrogen are called isotopes. All isotopes of a particular element have the same number of protons, but have a different number of neutrons. If you change the number of neutrons an atom has, you make an isotope of that element.Currently, scientists know of 118 different elements.Some, like gold, silver, copper and carbon, have been known for thousands of years.f you change the number of neutrons an atom has, you make an isotope of that element. Currently, scientists know of 118 different elements. Some, like gold, silver, copper and carbon, have been known for thousands of years.
Quick Answer. The isotopes of an element differ from each other in their mass numbers and the number of neutrons they contain. All of the isotopes of an element, however, contain the same number of protons, which is equal to that element's atomic number. The atomic number, because it does not reflect the number of neutrons in an atom, does not distinguish between the isotopes of a given element, which will all occupy the same position in the periodic table. Continue Reading