"Neither the enthalpy change nor the entropy change alone can be used

1.	"Neither the enthalpy change nor the entropy change alone can be used to explain the spontaneity of the reaction". Explain
Answer» Reaction are feasible in the direction of decrease in energy. Thus the reactions which proceed with a decrease in enthalpy (ΔH_negative) should be spontaneous. This is found to be so in many cases. However, there are some spontaneous reactions should process with an increase in entropy. Once again there are many spontaneous reactions which proceed with a decrease in entropy (ΔS_negative). Thus, it appears which explains the spontaneity of any reaction is called free energy change ΔG. This is related to ΔH and ΔS by the reaction. ΔG = ΔH - TΔS The reactions which proceed with negative ΔG are spontaneous.

"Neither the enthalpy change nor the entropy change alone can be used to explain the spontaneity of the reaction". Explain

Answer»

Reaction are feasible in the direction of decrease in energy. Thus the reactions which proceed with a decrease in enthalpy (ΔH_negative) should be spontaneous. This is found to be so in many cases. However, there are some spontaneous reactions should process with an increase in entropy. Once again there are many spontaneous reactions which proceed with a decrease in entropy (ΔS_negative).

Thus, it appears which explains the spontaneity of any reaction is called free energy change ΔG. This is related to ΔH and ΔS by the reaction.

ΔG = ΔH - TΔS

The reactions which proceed with negative ΔG are spontaneous.

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