Chemical Thermodynamics Question 280
Question: If the heat of combustion of carbon monoxide at constant volume and at $ 17^{o}C $ is - 283.3 kJ, then its heat of combustion at constant pressure $ (R=8.314,J,degre{{e}^{\text{-1}}}mo{{l}^{-1}}) $ [CPMT 2001]
Options:
A) - 284.5 kJ
B) 284.5 kJ
C) 384.5 kJ
D) - 384.5 kJ
Show Answer
Answer:
Correct Answer: A
Solution:
$ C{O_{(g)}}+\frac{1}{2}O_2_{(g)}\to C{O_{(g)}},\Delta n=1-1+\frac{1}{2}=-\frac{1}{2} $
$ \Delta H=\Delta E+\Delta nRT $
$ \Delta H=-283.3-\frac{1}{2}\times \frac{8.314}{1000}\times 290=-284.5kJ $ .
