One litre sample of a mixture of `CH_(4)` and `O_(2)` measured at `32^(@)C` and `760` torr, was allowed to react at constant pressure in a calorimeter. The complete combustion of `CH_(4)` to `CO_(2)` and water caused a temperature rise in calorimeter of `1K`. calculate mole `%` of `CH_(4)` in original mixture.
[Given: Heat of combustion of `CH_(4)` is `-210.8 Kcal//mol`. Total heat capacity of the calorimeter `= 2108 cal K`]

Answer

`25%`

Explanation

Heat generated `C_(1)DeltaT=1260xx0.667 cal`.
`:. n_(CH_(4))=(2.108xx1)/(210.8)=0.01`
`n_("total")=(PV)/(RT)=0.04" " :. mol%=(0.01)/(0.04)xx100=25%`