Chemical Thermodynamics Question 392
Question: From the following data AH of the following reactions
$ C(s)+\frac{1}{2}O_2(g)\xrightarrow{{}}CO(g); $
$ \Delta H=-110kJ $ and $ C(s)+H_2O(g)\xrightarrow{{}}CO(g)+H_2(g); $
$ \Delta H=132kJ $
Calculate the mole composition of the mixture of steam and oxygen on being passes over coke at 1273 K, keeping the temperature constant.
Options:
A) 1 : 0.6
B) 0.6 : 1
C) 2 : 3
D) 3 : 2
Show Answer
Answer:
Correct Answer: A
Solution:
- The first reaction is exothermic and the second reaction is endothermic. If on passing the mixture of $ O_2 $ and $ H_2O $ (steam) over coke while keeping the temperature constant $ \Delta H $ of both the reactions must be same. Moles of $ O_2 $ needed to evolve $ 132kJ $
$ =\frac{0.5\times 132}{110}=0.6 $
Hence steam: $ O_2 $ ratio must be 1 : 0.6
