Calculate the H_(3)O^(+) and OH^(-) ion concen- trations at 25^(@)C in(i) 0.02 N HCl solution (ii) 0.005 N NaOH solution

Calculate the H_(3)O^(+) and OH^(-) ion concen- trations at 25^(@)C in

1.	Calculate the H_(3)O^(+) and OH^(-) ion concen- trations at 25^(@)C in(i) 0.02 N HCl solution (ii) 0.005 N NaOH solution
Answer» Solution :(i) HCl completely ionizes as:`HCl + H_(2)O RARR H_(3)O^(+) + CL^(-)` `[H_(3)O^(+)]=[HCl]=0.02 N ` (Given) `0.02 M ` (`:'` HCl is monobasic) `=2xx10^(-2)M` Now, as `[H_(3)O^(+)][OH^(-)]=K_(w) = 10^(-14) :. [OH^(-)]=(K_(w))/([H_(3)O^(+)])=(10^(-14))/(2xx10^(-2))=5xx10^(-13) M` (ii) NaOH completely ionizes as `NaOH rarr Na^(+) + OH^(-)` `:. [OH^(-)]=[NaOH] = 0.005 N ` (Given) `=5xx10^(-3) M `(`:'` NaOH ismonoacidic) Now, as `[H_(3)O^(+)] [OH^(-)]=K_(w)=10^(-14) :. [H_(3)O^(+)]=(K_(w))/([OH^(-)])=(10^(-14))/(5xx10^(-3))=2xx10^(-12)M`