If the heat of combustion of carbon monoxide at constant volume and at `17^@`C is `-283.3`kJ, then its heat of combustion at constant pressure is _________ .
(R = 8.314 J `kelvin ^-1 mol^-1`)

Options

A. `- 284.5` kJ
B. 284.5 kJ
C. 384.5 kJ
D. `- 384.5 kJ`

Answer

A

Explanation

`CO_((g))+(1)/(2)O_(2(g))rarrCO_(2(g)), Deltan=1-1(1)/(2)=-(1)/(2)`
`DeltaH=DeltaE+DeltanRT`
`DeltaH=-283.3-(1)/(2)xx(8.314)/(1000)xx290=-284.5 kJ`