The enthalpy of formation for `C_(2)H_(4)(g),CO_(2)(g)` and `H_(2)O(l)` at `25^(@)C` and 1 atm. Pressure are 52, -394 and -286 KJ `mol^(-1)` respectively. The entahlpy of combustion of `C_(2)H_(4)` will be :-

Options

A. `+1412 "KJ mole"^(-1)`
B. `-1412 "KJ mole"^(-1)`
C. `+142.2 "KJ mole"^(-1)`
D. `-141.2 "KJ mole"^(-1)`

Answer

B

Explanation

`C_(2)H_(2(g))+3O_(2(g))rarr 2CO_(2(g))+2H_(2)O_((l)) , Delta H_("Comb.") = ?`
`Delta H = S?igma (Delta H_(f))_(P)-Sigma (Delta H_(f))_(R )`