The number of protons in a nucleus is the
A)mass number.
B)neutron number.
C)atomic number.
D)isotope number.
E)none of the above

Question

Quizplus · Accepted Answer

The atomic number of an element is defined as the number of protons in the nucleus of an atom. Therefore, the correct choice is (C). The mass number (A) is the total number of protons and neutrons in the nucleus, the neutron number (B) is the number of neutrons in the nucleus, and the isotope number (D) is not a recognized term in nuclear physics.

The Number of Protons in a Nucleus Is the