How do you find the atomic mass of magnesium?

1 Answer
Mar 3, 2017

Usually it is shown on a periodic table. If not, you have to add up the number of protons and neutrons in the atom if they are given.

Explanation:

If the number of protons and neutrons are not given, I am not sure how to find the atomic mass.

My periodic table shows that it is 24.305 amu. In AP Chemistry I have always been allowed to see a periodic table on any test that gives me the atomic mass, atomic number, symbol, and electronegativity. I'm not sure how to find it otherwise.

I hope this helps!