A) \[~\text{26}.\text{4 kcal}\]
B) \[-\text{26}.\text{4 kcal}\]
C) \[~\text{41}.\text{2 kcal}\]
D) \[-\text{41}.\text{2 kcal}\]
Correct Answer: B
Solution :
According to Hess's law, the total heat changes occuring during a chemical reaction are independent of path. \[2CO(g)+{{O}_{2}}\to 2C{{O}_{2}}(g),\] \[\Delta H=-135.2\text{kcal}\] \[C{{O}_{2}}(g)\to CO+\frac{1}{2}{{O}_{\,}}_{2}(g),\] \[\Delta H=\frac{135.2}{2}\text{kcal}\] ? (i) \[C+{{O}_{2}}(g)\to C{{O}_{2}}(g),\] \[\Delta H=-94\text{kcal}\] ? (ii) Required equation \[C(s)+\frac{1}{2}{{O}_{2}}(g)\to CO(g),\Delta H=?\] Adding Eqs. (i) and (ii), we get \[\text{C(s)+}\frac{\text{1}}{\text{2}}{{\text{O}}_{\text{2}}}\text{(g)}\to \text{CO(g), }\!\!\Delta\!\!\text{ H=-26}\text{.4kcal}\]You need to login to perform this action.
You will be redirected in
3 sec