What is the percentage by mass of hydrogen in ethanoic acid?

1 answer

The chemical formula of ethanoic acid is CH3COOH. It contains two atoms of hydrogen in each molecule. The atomic weight of hydrogen is 1.008 g/mol, and the molecular weight of ethanoic acid is 60.05 g/mol.

Therefore, the percentage by mass of hydrogen in ethanoic acid can be calculated as follows:

Mass of hydrogen = 2 x 1.008 g/mol = 2.016 g/mol
Mass of ethanoic acid = 60.05 g/mol

Percentage by mass of hydrogen = (mass of hydrogen / mass of ethanoic acid) x 100
= (2.016 g/mol / 60.05 g/mol) x 100
= 3.36%

Therefore, the percentage by mass of hydrogen in ethanoic acid is 3.36%.