1.   This states that the total entropy of a system and its surroundings increases during all spontaneous processes.

2.   The second law requires that the total entropy of a system and its surroundings increases during a spontaneous process.

3.   We are thus able to calculate the total entropy change which accompanies a chemical change and see whether the result obeys the second law of thermodynamics.

4.   SOLUTION The total entropy change accompanying a process is given by equation.

5.   In conclusion, although the enthalpy change for the reaction system is negative, the total entropy change which accompanies the reaction is positive.