acids and bases

[Sheldon]

How does the sub-atomic particles give the sodium atom its mass?

[deleted-279800]

Atoms are made up of three basic types of subatomic particles: protons, neutrons, and electrons. Most of the mass of an atom comes from the protons and neutrons, which make up the nucleus at the center of the atom. (Electrons don’t add much to the mass of an atom.)

A sodium atom has 11 protons and 12 neutrons. If you know the number of protons and neutrons in an atom, you can calculate its mass number by adding the two numbers together. The answer you get is the mass of the atom in atomic mass units or “amu”.

You can find out more information on these sites:
http://www.chemicalelements.com/elements/na.html
https://www.nde-ed.org/EducationResourc ... number.htm

There is also an atom’s average atomic mass, which is based on the different isotopes of the atom found in nature. You can read more about calculating the average atomic mass here:

https://www.boundless.com/chemistry/tex ... -218-3703/