A cylinder of cooking gas contains 14.0 kg of butane. If a family needs 20,000kJ of energy per day for cooking, how long will the cylinder last? The enthalpy of combustion of butane is -2658 kJ `mol^-1`

A cylinder of cooking gas is assumed to contain 14.2 kg butane (C_(4)H_(10)) combustion of butane is C _(4) H _(10 (g)) + (13)/(2) O _(2 (g)) to 4CO _(2 (g)) + 5 H _(2) O _((l)) , Delta H =- 1660 kJ If a family needs 14000 kJ of energy per day for cooking and assuming that 20% of the gas is wasted due to incomplete combustion, how long would the cylinder last?

If LPG cylinder contains a mixture of butane and isobutane, then the amount of oxygen required for the complete combustion of 1 kg of the mixture will be