What is the molecular mass of sulphuric acid (H2SO4)? (Atomic masses: H = 1 u, S = 32 u, O = 16 u)
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 98 u
The molecular mass of a substance is the sum of the atomic masses of all the atoms in one molecule. One molecule of H2SO4 has 2 hydrogen atoms, 1 sulphur atom and 4 oxygen atoms.
Mass of 2 H \(=2\times1=2\,\mathrm{u}\)
Mass of 1 S \(=32\,\mathrm{u}\)
Mass of 4 O \(=4\times16=64\,\mathrm{u}\)
Molecular mass of H2SO4 \(=2+32+64=98\,\mathrm{u}\)