Question

What is the difference between molecular mass and empirical mass? Explain with the help of hydrogen peroxide molecule.

Answer 1

Molecular mass is the sum of masses of the total number of species in the molecule.
Empirical mass is calculated using empirical formula which is the simplest whole number ratio of the molecular formula.
Molecular formula of Hydrogen peroxide = ${\text{H}}_2{\text{O}}_2$
Thus, Molecular mass = (2 x1 + 16 x2) = 34.
Empirical formula of Hydrogen peroxide = $\text{H}O$
Thus, Empirical mass = (1 x1 + 16x 1 ) = 17.