2. Write the equilibrium expression for HF + H2O → F- + H3O+

(i) Find [H+] of a 0.056 M hydrofluoric acid solution. Ka = 1.45 x 10-7

(ii) Then calculate the pH

3. Write the equilibrium expression for NH3 + H2O → NH4+ + OH-

4. Write the equilibrium expression for H2S + H2O → H3O+ + HS- and

(i) Calculate the [H3O+] in a 0.45 M solution of hydrogen sulphide (H2S). Ka = 2.05 x 10-6,

(ii)Then calculate the pH of H2S?

5. Write the equilibrium expression for NH3 + H2O g NH4+ + OH-

(i) Calculate the [OH-] in a 0.60 M solution of ammonia (NH3) Kb = 6.83 X 10-4,

(ii)Then calculate the pHof NH3 (Base)

6. The pH in a 0.25 M solution of the acid HBrO is 4.65 . Using this, Write the equilibrium expression of
HBrO and calculate the value of Ka for the acid HBrO