EASY
AS and A Level
IMPORTANT
Earn 100

The standard free energy change of formation of ethane is -32.9 kJ mol-1. The standard entropy change of the system for this reaction is -173.7 J K-1 mol-1.

Explain why the reaction can be feasible, even though the value of the standard entropy change of the system is negative.

Important Questions on Entropy and Gibbs Free Energy

EASY
AS and A Level
IMPORTANT

Ethane undergoes combustion to form carbon dioxide and water.

C2H6g+72O2g2CO2g+3H2Ol

Calculate the free energy change of combustion for this reaction.

Values of Gf in kJ mol-1:C2H6g=-32.9, CO2g=-394.4, H2Ol=-237.2.

 

EASY
AS and A Level
IMPORTANT

Calculate the standard entropy change of the system in the given below reaction using the standard molar entropy values given here. (Values for Sin J K-1 mol-1).

Given:

H2O2l=109.6H2Ol=69.90O2g=205.0

2H2O2l2H2Ol+O2g