How is the mass number related to the number of protons and neutrons an atom has?

1 Answer
David Drayer
Mar 20, 2018

The mass number of an individual atom is the sum of the protons and the neutrons.

Explanation:

The proton has a mass of approximately 1 amu
The neutron has a mass of approximately 1 amu
The electron has a mass of several orders of magnitude less than 1 amu. The mass of the electrons can be ignored when calculating the total mass of the atom.

# p + n = mass #

Related questions
See all questions in Mass Number
Impact of this question
14657 views around the world
You can reuse this answer
Creative Commons License