Question

If delta H=-50.0kJ and deltaS=-0.500 kj/k, the reaction is spontaneous below a certian temperature. Calculate the temperature

express your answer numerically in kelvins

Answer 1

ΔG = ΔH -TΔS
For spontaneous reaction ΔG <0,
if the reaction is at equilibrium then the ΔG = 0;

Given, ΔH = -50.0 kJ
       ΔS = -0.5 KJ/K
      
therefore, ΔG = -50.0 KJ - T. (-0.5 KJ/K)

at equilibrium ; 0 = -50.0 KJ - T. (-0.5 KJ/K)
               - T. (-0.5 KJ/K)= 50 KJ
               T = 50 KJ/0.5 KJ/K
                  = 100 K
Therefore, the reaction is at equilibrium at 100K and the reaction will be spontaneous below 100 K.

Hence, the reaction is spontaneous below 100K.