Question

What does the atomic mass equal to?
An average of the masses of the isotopes.
A whole number representing the number of protons

Answers

GPT-4o mini
The atomic mass of an element is the weighted average of the masses of its isotopes, which takes into account the relative abundance of each isotope. It is usually expressed in atomic mass units (amu).

So, among the options you provided, the correct description is:

**"An average of the masses of the isotopes."**

The other option, "A whole number representing the number of protons," describes the atomic number, not the atomic mass. The atomic number is the number of protons in the nucleus of an atom and is usually a whole number.