Description : How many protons and neutrons are in isotopes of magnesium?
Last Answer : The number of protons (p+) in the nuclei of an element's atoms is the atomic number of the element. In this case, the atomic number of magnesium is 12. In a neutral atom, the number of electrons (e-) equals the number of ... .Magnesium-26: 26 - 12 = 14; An atom of Mg-26 has 12 p+, 12 e-, and 14 n0.