QQuestion
A gas cylinder can hold 150 g of hydrogen under certain conditions of temperature and pressure. If an identical cylinder with the same capacity can hold 450 g of gas ‘G’ under the same conditions of temperature and pressure, find:
(a) the vapour density of the gas ‘G’.
(b) the molecular weight of gas ‘G’.
✓Answer
(a) V.D. = mass of certain volume of gas under similar conditions / mass of equal volume of H2 under similar conditions
= 450\over150 = 3
(b) Molecular weight = 2 × V.D.
= 2 × 3 = 6 a.m.u.
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