Question

`50mL` of `0.05M` Propane `-1,2-`diamine solution is titrated with `0.1M HCl` solution at `25^(@)C`. Detemine the `pH` of solution obtained by adding following volumes of `HCl` solution.

Answer 1

(a) Half neutralisation :`pH=pK_(a_(1))=14-4.18=9.82`
(b)`pH=((pK_(a_(1))+pK_(a_(2)))/(2))=(14-4.18+14-7.39)/(2)=8.215`
(c ) Buffer: `pH=14-7.39+log((2.5-0.5)/(0.5))=7.21`