The atomic mass of an element
A) is determined by the number of protons and neutrons contained in the nucleus.
B) equals the number of protons plus the number of electrons.
C) equals the number of neutrons.
D) changes after each reaction.
E) depends on the number of electrons in the outermost shell.

Question

Quizplus · Accepted Answer

The atomic mass of an element is determined by the number of protons and neutrons contained in the nucleus, which are also known as the element's mass number. The number of electrons does not affect the atomic mass, as they have negligible mass compared to protons and neutrons. The atomic mass remains constant for a particular element, even after chemical reactions, as the number of protons and neutrons in the nucleus do not change during chemical reactions.

The Atomic Mass of an Element