Chemical Thermodynamics Question 479
Question: The gaseous endothermic reaction : $ P+Q\to 3R $ at $ 327{}^\circ C $ takes place spontaneously, because-
Options:
A) $ \Delta H<0;,\Delta S<0 $
B) $ \Delta H>0;,\Delta S>0 $
C) $ \Delta H<0;,\Delta S>0 $
D) $ \Delta H>0;,\Delta S<0 $
Show Answer
Answer:
Correct Answer: B
Solution:
- $ \Delta G=\Delta H-T\Delta S $
For an endothermic reaction $ \Delta H=+ve $
[less molecules $ \to $ more molecules],
$ \Delta H=+ve $
$ \therefore $ $ T\Delta S>\Delta H, $ and $ \Delta G=-ve $
Hence, the reaction occurs spontaneously.