The nuclei of different isotopes of a given element have the same number of
A) protons.
B) neutrons.
C) nucleons.
D) electrons.
E) positrons.

Question

Quizplus · Accepted Answer

Isotopes of a given element have the same number of protons, which is a defining characteristic of the element. The number of neutrons may vary between isotopes, which affects their atomic mass, but the number of protons is always constant. Nucleons refers to both protons and neutrons, so while it is true that isotopes of a given element have the same number of nucleons, this is not the best choice because it is not specific to protons. Electrons and positrons are not found in the nucleus, so these choices are incorrect.

The Nuclei of Different Isotopes of a Given Element Have