Find the molar mass and divide by it

Use the smallest # of moles to set up mole ratios for the remaining elements

Use the smallest atomic mass to set up molar ratios for the remaining ratios.

Mass Percent

Mass Percent of a Hydrate

Empirical Formula

Molecular Formula

Multiply the molar mass by each individual element's atomic mass

Divide each element's individual atomic mass by the molar mass

Divide the molar mass by the lowest molar ratio

Mass Percent

Mass Percent of a Hydrate

Empirical Formula

Molecular Formula

Multiply by each element's atomic mass by the molar mass

Divide the experimental mass (given in the problem) by the molar mass

Multiply the experimental mass (given in the problem) by the molar mass

Mass Percent

Mass Percent of a Hydrate

Empirical Formula

Molecular Formula