Question

Why is it more convenient to predict spontaneity of reaction in terms of ΔGsys rather thar ΔStotal?

Answer 1

However, spontaneity in chemistry is a little different concept. It is a vital concept in Thermodynamics of chemical reactions. ... For a spontaneous process, the total entropy change, ΔS total is always

Answer 2

It is due to the spontaneity in the part of the chemistry which is little various over the concepts.

Then it has right and vital concepts in the part of the thermodynamics of the chemical reaction in a fine manner.

Therefore the spontaneous method is completely entropy change and ΔS become is always in a fine manner.