The molar mass of a substance is the mass of one mole of that substance. To find molar mass, you need to know the formula weight (the number of atoms in one molecule) and how many grams are in one mole.

The formula weight is determined by adding up the atomic weights of all the elements in the compound. For example, water has a formula weight of 18 because it’s made up of two hydrogen atoms (1 proton and 1 electron each) and one oxygen atom (8 protons and 8 electrons).

To find the number of moles of a substance, you divide its mass by its molecular weight. For example, if you have 100 grams of CO(NH) (molecular weight = 28 g/mol), divide this by 28 g/mol. This gives you 3.5 moles.

Last modified: July 31, 2022