Calculating molecular weights

The molecular weight Mw of a molecule can be found by adding the atomic weights of all the atoms that molecule is made of. Let’s take Sulfuric Acid as an example. The formula of Sulfuric Acid is H2SO4. To calculate the molecular weight we take:

The equation for calculating the atomic mass of sulfuric acid. Two times atomic mass of hydrogen plus atomic mass of sulphur plus 4 times atomic mass of oxygen is equal to two times 1.01 amu plus 32.06 amu plus 4 times 16 amu, which is equal to 98.08 amu.

Just like the atomic mass in amu corresponds to the molar mass of that atom in grams, so the molecular weight of one molecule in amu corresponds to the molar mass in g/mol.

Referred from:

Article

Moles and Avogadro's number