Ultrashnotebel Posted May 20, 2018 Share Posted May 20, 2018 The question is simply to predict the reaction product of S2- and NH4+, and find its equilibrium constant. We have access to the Ka of H2S (which is the Ka of HS-) and the Kb of NH3.second HS- + H2O -> S2- + H3O+ ka = 1.1x10-12 => kb = kw/ka = 9.1.10^sup]-3[/sup] which is the equilibrium constant for the reaction: S2- + H2O -> HS- + OH-NH3 + H2O -> NH4+ + OH- kb = 1.774x10-5 => ka = kw/kb = 5.637x10-10 which is the equilibrium constant for the reaction: NH4+ + H2O -> NH3 + H3O+ Adding those two reactions together, we find: S2- + NH4+ + 2H2O -> HS- + NH3 + OH- + H3O+And so by multiplying the constants, we get 51.3x10-13... Which is not at all the answer I'm given. Somehow, the answer is 510. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now