dessicantsdrying agents can often be regenerated

Question

Dessicants(drying agents) can often be regenerated by heating.  A dessicant that is commonly regenerated is CaSO₄.2H₂O:                                                                      

CaSO₄.2H₂O(s) → CaSO₄(s) + 2H₂O(g)

 

    H^o = 25.1 kJ/mol; ?S^o = 69.3 J/molK

       Regeneration is carried out at 250 ^oC.

(a)    What is the ?G^o for this reaction?

(b)   What is the equilibrium constant at 25 ^oC?

(c)    What is the ratio K_{250 C}/K_25C?

(d)   What is the equilibrium constant at 250 ^oC

(e)    Is regeneration of this dessicant an enthalpy- or entropy-driven process?  Explain your answer.