The standard enthalpies fo formation of `CO_(2) (g), H_(2) O (1)`, and glucose (s) at `25^(@)C` are `- 400 kJ mol^(-1), - 300 kJ mol^(-)`, and `- 1300 kJ mol^(-1)`, respectively. The standard enthalply of combustion per gram of glucose at `25^(@)C` is

Options

A. `+2900 kJ`
B. `-2900 kJ`
C. `-16.11 kJ`
D. `+16.11 kJ`

Answer

C

Explanation

`C_(6)H_(12)O_(6)(s)+6O_(2)(g)to2CO_(2)(g)+6H_(2)(l)`
`Delta_(f)^(@)=DeltaCH^(@)=[6DeltafH^(@)(CO_(2))+6DeltaH_(f)^(@)H(H_(2)O)_(6)]-[Delta^(@)(C_(6)H_(12)O_(6))+6DeltafH^(@)*O_(2)]`
`=6xx(-400)+6xx(-300)-(1300)`
`=-2900 kJ//mol`
`=-(2900)/(180)kJ//g=16.11 kJ//g`