what is the atomic mass for magnesium
This formula shows that each formula unit contains one magnesium atom. â¦ The gram atomic mass of magnesium is 24.305. Therefore, the percentage by mass of magnesium in this magnesium nitrate dihydrate is 100(24.305/184.35) or 13.038 %, to the justified number of significant digits. Answered. In Elements and Compounds.