Chemistry · Introduction to Fundamental Concepts of Chemistry
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Isotopes differ in:
- A
Proton Number
- B
Neutron Number
- C
Atomic Number
- D
Electron Number
Isotopes are variations of the same chemical element that have the same number of protons, and therefore the same atomic number, but differ in the number of neutrons. This difference in neutron count results in variations in atomic mass but not in chemical behavior, as the chemical properties are determined by the electron configuration, which remains unchanged. Options A and C are incorrect because they refer to protons, which determine the element itself, not its isotopes. Option D is incorrect because electron variation leads to ions, not isotopes.
This option is incorrect because isotopes have the same number of protons. Changes in proton number result in different elements, not isotopes.
Correct! Isotopes of an element have the same number of protons but differ in the number of neutrons, which affects their atomic mass.
Incorrect. The atomic number is defined by the number of protons in an atom. Isotopes share the atomic number but differ in neutron count.
This option is incorrect because differing numbers of electrons result in ions, not isotopes. Isotopes have the same electron number as well.
Tagged under Chemistry · Introduction to Fundamental Concepts of Chemistry · 2006