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.
Atoms of an element usually have the same number of neutrons as protons. Atoms of the same element that have a different number of neutrons are called isotopes. Isotopes have the same atomic number but different atomic masses. Atoms of an element share that element's chemical and physical properties, such as boiling point, melting point and stability. An element is the simplest form of matter and cannot be broken down further by chemical means.