[wintaer]

We're given information (A, activation energy, Temperature) to calculate the rate constants for two rxns:

(NH4)2S (s) --> 2 NH3(g) + H2S(g)
2 NH3(g) + H2S(g) --> (NH4)2S(s)

How do I use it to calculate the equilibrium constant (K) for: (NH4)2S (s) <--> 2 NH3(g) + H2S(g) ?

Thanks!

[Astrokel]

Consider the rate of forward reaction and rate of backward reaction at equilibrium, write the two rate equations out and you will see.