The formula mass of a substance is the sum of the average atomic masses of each atom represented in its emperical formula and is expressed in atomic mass units (amu).

Example and Calculation

The molecular formula for glucose is C_{6}H_{12}O_{6}
So, the empirical formula is CH_{2}O.

The formula mass of glucose is 12+2(1)+16 = 30 amu.

## Shrestha

## Formula Mass

The formula mass of a substance is

the sum of the average atomic masses of each atom represented in its emperical formulaand is expressed in atomic mass units (amu).## Example and Calculation

The molecular formula for glucose is C

_{6}H_{12}O_{6}So, the empirical formula is CH

_{2}O.The formula mass of glucose is 12+2(1)+16 = 30 amu.