Question

What is the molecular mass of sulphur dioxide (${\text{SO}}_2$)?

• A. 16 u
• B. 48 u
• C. 32 u
• D. 64 u

Answer 1

The correct option is D 64 u

Molecular mass of a substance is the sum of the atomic masses of its constituent atoms.
Molecular mass of (${\text{SO}}_2$)
= Atomic mass of S + [2 x (Atomic mass of O)]
= 32 + (2 x 16)
= 64 u.