For the chemical equilibrium, CaCO (s) CaO(s) CO (g) , Hº can be determined from which one of the following graphs ? (a) (b) (c) (d)

It is a plot of 2 CO 1 ln P vs T 2 C 2 2 2 AB K = A B 2x 4 4 2 x 4 x 4 4 But 2 P CO K = P Hence, 2 o r CO H ln[p ] ln A RT For plot of 2 CO 1 ln P vs T , the slope is ° R ΔH R . Option (a) depicts the correct graph.