An element's mass number tells us which of the following?
A) The number of protons in an atom of that element.
B) The number of protons + electrons in an atom of that element.
C) The number of electrons in an atom of that element.
D) The number of protons + neutrons in an atom of that element.
E) The number of neutrons in an atom of that element.

Question

Quizplus · Accepted Answer

The mass number of an element is the sum of the number of protons and neutrons in the nucleus of an atom.

An Element's Mass Number Tells Us Which of the Following