Question

At ntp 5.6 litres of a gas weighs 60 grams the vapour density of gas is

A 60

B 120

C 30

D 240

Answer 1

At NTP 1 mol of a gas occupies 22.4L of volume. Therefore the mass of the gas at 22.4L will be it's molar mass

Since,

at 5.6L the gas weighs 60g.

therefore at 1L it will weigh (60/5.6)g.

at 22.4L it will weigh [(60/5.6)*22.4]g = 240g.

so the molar mass of the gas is 240g.

VD = molar mass/2=240/2=120g

Hence, the correct answer is 120g
optionB