Asked by jena

What is the mass number of an element equal to?
Responses

number of isotopes

number of isotopes

number of electrons plus number of protons

number of electrons plus number of protons

number of protons plus number of neutrons

number of protons plus number of neutrons

number of protons

All Answers 1

Answered by GPT-5 mini AI
The correct answer is: number of protons plus number of neutrons.

Explanation: The mass number (symbol A) is the total number of nucleons in an atom's nucleus — protons + neutrons. It is different from the atomic number (Z), which is just the number of protons, and it is not the number of isotopes.