The ratio of heats liberated at 298 K from the combustion of one kg of coke and by burning water gas obtained from kg of coke is (Assume coke to be 100% carbon). (Given enthalpies of combustion of `CO_2`, CO and `H_2` as 393.5 kJ, 285 kJ, 285 kJ respectively at 298 K).

Options

A. `0.79:1`
B. `0.69:1`
C. `0.86:1`
D. `0.96:1`

Answer

B

Explanation

Given information, the enthalpy of combustion of `CO_(2)` is wrong, it should be enthalpy of combustion of C.
1kg of coke `= (1000)/(12)=83.33` moles
`C+O_(2) rarr underset(83.33xx393.5 kJ)(CO_(2))`
`underset("Water gas")ubrace(CO+H_(2))+O_(2)rarr underset(83.33xx570kJ)underset(83.33xx393.5kJ)(CO_(2))`
Now, the ratio of
`{:(,"coke",:,"water gas",),(,83.33xx393.5,:,83.33xx570,),(rArr,393.5,:,570,),(rArr,0.69,:,1,):}`