Assume that for a domestic hot water supply `150 kg` water per day must be heated from `10^(@)C` to `65^(@)C` and gaseous fuel propane `C_(3)H_(8)` is used for this purpose. What moles and volume of propane (in `L` at `STP)` would have to be used for heating domestic water, `DeltaH` for combustion of propane is `-2050kJ mol^(-1)` and specific heat of water is `4.184 xx 10^(-3) kJ g^(-1)`.

Explanation

Heat teken up by water `=msDeltaT`
`=150 xx 103 xx 4.184 xx 10^(-3) xx55 = 34518 kJ`
`2050 kJ` heat is provided by `1mol C_(3)H_(8)`
Therefore, `34158 kJ` heat is provided by `34518//2050 = 16.838 mol of C_(3)H_(8)`
Therefore, volume of `C_(3)H_(8)` at `NTP`
`= 16.838 xx 22.4L = 377.17 L`