An aqueous solution contains a mixture of 0.100 M HCl and 0.100 M HNO2. Which acid makes a negligible contribution to the pH and why is this?
Ka HNO2= 4.0x10E-4
Kb= NH3=1.8x10E-5
Ans.
HCl is a strong acid with Ka of 1.3 x 106 whereas, HNO2 is a weak acid with Ka of 4.0 x 10-6.
Therefore, HCl dissociates far more compared to HNO2. The more the dissociation, the higher is the contribution of H3O+ to the aqueous solution. HNO2, being a weak acid contributes small amount of H3O+and has negligible effect on the pH.
An aqueous solution contains a mixture of 0.100 M HCl and 0.100 M HNO2. Which acid...