The density of a certain gas is 1.98gdm-3 at s.t.p. What is the molecular mas of the gas?

The density of a certain gas is 1.98gdm^-3 at s.t.p. What is the molecular mas of the gas?

Correct Answer: Option A

Explanation:
Density = mass/volume
âˆ´ 1.98 = molecular mass/22.4
molecular mass = 1.98 * 22.4 = 44.35 â‰… 44.05