`Delta_(f)^(@)` for `CO_(2(g)), CO_((g))` and `H_(2)O_((g))` are `-393.5,-110.5` and `-241.8kJ mol^(-1)` respectively. The standard enthalpy change `(` in `kJ)` for given reaction is `:`
`CO_(2(g))+H_(2(g)) rarr CO_((g))+H_(2)O_((g))`

Options

A. `+524.1`
B. `+41.2`
C. `-262.5`
D. `-41.2`

Answer

B

Explanation

Given,
`C+O_(2) rarr CO_(2), DeltaH^(@)=-393.5kJ ….(1)`
`C+(1)/(2)O_(2) rarr CO, DeltaH^(@)=-110.5kJ ….(5)`
`ul (H_(2)+(1)/(2)O_(2)rarr H_(2)O, DeltaH^(@)=-241.8kJ ....(3))`
`CO_(2)+H_(2) rarr CO+H_(2)O,DeltaH^(@)=+41.2`
By `(2)+(3)-(1)`
`DeltaH^(@)=+41.2`