The standard enthalpy of formation of octane `(C_(8)H_(18))` is `-250kJ //mol`. Calculate the enthalpy of combustion of `C_(8)H_(18)`. The enthalpy of formation of `CO_(2)(g)` and `H_(2)O(l)` are `-394 kJ//mol` and `-286kJ//mol` respectively.

Options

A. `-5200kJ//mol`
B. `-5726 kJ//mol`
C. `-5476 kJ//mol`
D. `-5310kJ//mol`

Answer

C

Explanation

`Delta H^(@) = 8 xx (-394)+9 xx (-286)-(-250)`
`= -5476 kJ//mol`