Two nuclei may have equal Z, but different A, because they contain
A) equal numbers of protons and neutrons.
B) equal numbers of protons but different numbers of neutrons.
C) different numbers of protons but equal numbers of neutrons.
D) different numbers of protons and neutrons.
E) electrons as well as neutrons.

Question

Quizplus · Accepted Answer

Since the nuclei have equal Z, they contain the same number of protons. However, they have different A, which means they have different numbers of neutrons. Therefore, option B is the correct one.

Two Nuclei May Have Equal Z, but Different A, Because