Given , pH = 12, 100 ml + pH = 3, 900 ml .Fiind the net pH of the mixture.(answers :- pOH = 4 and pH = 10)

PH = 12 i.e. H+ ion con 10^(-12) or OH- ion concentration be 10^(-4)...Total of 100 ml gives total of 10^(-2) mili mol of OH- ions.Now pH = 3, i.e. H+ ion con be 10^(-3) an total of 900 ml. Gives 0.9 mili mol of H+ ions Which will react with .01 mol of OH- ions to form water and total of (0.9-.01= .89) mol of H+ ion in 1000 ml of solution. So H+ ion concentration will be (.9mmol/) = 9*10^(-4) so pH will be =3.045

Approved