Question

The volume of a gas mixture obtained by heating 1 litre CO2 gas with graphite is 1.5 liter at stp.

What is the number of moles of CO gas at stp in this mixture?




Answer- 1/22.4

Answer 1

you know as well, graphite is purest form of carbon. now reaction of carbon dioxide with graphite is ....

$CO_2+C\rightarrow 2CO$

here it is clear that,

1 mole of CO2 gas produces 2 moles of CO.

at STP , 1 mole of gas = 22.4 Litres.

so, 22.4Litres of CO2 gas gives 2(22.4) = 44.8 litres of CO gas.

or, 1 Litre of CO2 gas gives 2 litres of CO2 gas.

hence, ratio of volume of CO2 and CO = 1 : 2

but volume of mixture of CO and CO2 is 1.5

so, volume of CO gas = 1.5 × 2/(1 + 2) = 1litre.

now, no of mole of CO gas at STP = volume of CO gas/22.4

= 1/22.4 [ answer ]