Chemical Thermodynamics Question 183
Question: The heat of formations of $ CO(g) $ and $ CO_2(g) $ are $ -26.4 $ kcal and $ -94.0 $ kcal respectively. The heat of combustion of carbon monoxide will be [MP PET/PMT 1988; EAMCET 1993]
Options:
A) $ +26.4,kcal $
B) $ -67.6,kcal $
C) $ -120.6,kcal $
D) $ +52.8,kcal $
Show Answer
Answer:
Correct Answer: B
Solution:
Aim: $ CO+\frac{1}{2}O_2\to CO_2 $
$ \Delta H=\Delta H_{f}^{0},(CO_2)-[ \Delta H_{f}^{0}(CO)+\frac{1}{2}\Delta H_{f}^{0}(O_2) ] $
$ =-,94.0-(-26.4)=-67.6kcal. $