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Highly selective Backlog Qs for JEE MainChemistryThermodynamics (C)

In isolated system, find the condition for spontaneous reaction.

Options

  1. AU=0, S=0, G=0
  2. BU < 0, S>0, G < 0
  3. CU=0, S>0, G < 0
  4. DU < 0, S < 0, G < 0

Correct answer

C. U=0, S>0, G < 0

Step-by-step solution

For an isolated system, q=0, w=0 aligned & U=0 & G= H-T S aligned For spontaneous reaction, G=-v e. H=0 for an isolated system. Thus, S>0 for the reaction to be spontaneous.

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