The molar mass of the chemical substance is equal to the sum of the atomic mass of the individual atoms. The smallest unit of a compound is molar mass, which is one-twelfth of the mass of one carbon atom – 12 atoms.
- The notion of molar mass can be used to calculate how many grams of substance are necessary when we know the number of moles required.
- The molar mass, also known as molecular weight, is the sum of all the atoms that make up a mole of a molecule’s total mass in grams. The unit of measurement is grams per mole.
- Atomic mass of H = 1u
- Atomic mass of N = 14 u
- Atomic mass of O = 16u
The molar mass of HNO3 is
(1 × 1) +(1 × 14) + (16×3) = 63 u.