Question

The gases chlorine, nitrogen, ammonia and sulphur dioxide are collected under the same conditions of temperature and pressure. The following table gives the volumes of gases collected and the number of molecules (x) in 20 litres of nitrogen. You are to complete the table giving the number of molecules in the other gases in terms of x.

Gas	Volume (in litres)	Number of molecules
Chlorine	10	x
Nitrogen	20
Ammonia	20
Sulphur dioxide	5

Answer 1

Gas	Volume (in litres)	Number of molecules
Chlorine	10	`"x"/2`
Nitrogen	20	x
Ammonia	20	x
Sulphur dioxide	5	`"x"/4`

According to 'Avogadro's Law, "Equal volumes of all gases, under similar conditions of temperature and pressure, contain equal number of molecules."

∴ 20 lit. nitrogen contains x molecules

∴ 10 lit. of chlorine will contain = `(x xx 10)/20`

= `x/2` mole

and 20 lit. of Ammonia will also contain = x molecules

and 5 lit. of SO₂ will contain = `(x xx 5)/20`

= `x/4` mole