From the following enthalpies of combution, deduce which of the quoted expressions gives the heat of formation at a fixed temp. C(s) +O_(2) (g) rarr CO_(3)(g) , DeltaH=c H_(2)(g)+1//2O_(2)(g) rarr H_(2)O(l),Delta =h CH_(4)(g)+2O_(2)(g) CO_(2)(g)+2H_(2)O(l),Delta H=m

From the following enthalpies of combution, deduce which of the quoted

1.	From the following enthalpies of combution, deduce which of the quoted expressions gives the heat of formation at a fixed temp. C(s) +O_(2) (g) rarr CO_(3)(g) , DeltaH=c H_(2)(g)+1//2O_(2)(g) rarr H_(2)O(l),Delta =h CH_(4)(g)+2O_(2)(g) CO_(2)(g)+2H_(2)O(l),Delta H=m
Answer» c+h-m c-h+m c+2h-m `-1//2`c-h+1/2 m Solution :`C(s) +2H_(2)(G) to CH_(4) ""DeltaH_(f)=?` To OBTAIN this equation (i) + 2 `xx (II)-(III)` `DeltaH_(f)=c+ 2h-m`