The atomic mass (mass number) of an atom is determined by the combined masses of its
A) neutrons and protons.
B) neutrons and electrons.
C) protons and electrons.
D) protons, neutrons, and electrons.
E) neutrons, nucleus, and electrons.

Question

Quizplus · Accepted Answer

The atomic mass (mass number) of an atom is determined by the combined masses of its neutrons and protons, as electrons have a negligible mass compared to protons and neutrons.

The Atomic Mass (Mass Number) of an Atom Is Determined