`1.0`litre sample of a mixture of `CH_(4)` and `O_(2)` measured at `25^(@)C` and `740 ` torr, was allowed to react at constant pressure in a calorimeter, together with its contents had a heat capacity of `1260 cal K^(-1)`. The complete combustion of `CH_(4)` to `CO_(2)` and water caused a temperature rise in calorimeter of `0.667K`. Calculate mole `%` of `CH_(4)` in the original mixture. Heat of combustion of `CH_(4)` is `-210.8 kcal. `

Explanation

`10.0` mol % `CH_(4)`