Engineering Board Exam Reviewer · Chemistry · medium

A reaction is spontaneous at all temperatures when:

  1. H < 0 and S > 0
  2. H > 0 and S < 0
  3. H > 0 and S > 0
  4. H < 0 and S < 0

Answer

A. H < 0 and S > 0

Solution

G = H - T S is then always negative.

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