For a particular reaction, ΔH = -99.84 kJ and ΔS = -16.80 J/K. Calculate ΔG for this reaction at 298 K.

Question

Hello, anybody able to help me out and explain this problem to me?

 

For a particular reaction, ΔH = -99.84 kJ and ΔS = -16.80 J/K. Calculate ΔG for this reaction at 298 K.

 

What can be said about the spontaneity of the reaction at 298 K?

Answer 1

G = H - TS

 

ΔG = ΔH - TΔS

 

You are given ΔH, ΔS, and T.  Compute ΔG from the formula above, being careful with units and signs.  The natural direction of a reaction is to move toward equilibrium.  ΔG is negative as you move toward equilibrium.  Therefore, if ΔG is negative, the reaction can be spontaneous.  If ΔG is positive, it is not spontaneous.  I think you can answer the question now.