Chemical Thermodynamics Question 345
Question: Following reaction occurrs in an automobile $ 2C_8H_{18}( g )+25O_2( g )\to 16CO_2( g )+18H_2O( g ). $ The sign of $ \Delta H,\Delta S $ and AG would be
Options:
A) $ +,-,+ $
B) $ -,+,- $
C) $ -,+,+ $
D) $ +,+,- $
Show Answer
Answer:
Correct Answer: B
Solution:
For combustion reaction, $ \Delta H $ is negative, $ \Delta n=( 16+18 )-( 25+2 )=+7 $ , so $ \Delta S $ is +ve, reaction is spontaneous, hence $ \Delta G $ is -ve.
