Calculate normality of the mixture obtained by mixing 100 ml of 0.1 N HCl and 50 ml of 0.25 N NaOH solution.

Meq. of HCl =100×0.1=10Meq. of NaOH =50×0.25=12.5∴ HCl and NaOH neutralize each other with equal equilents. Meq. of NaOH left = 12.5 - 10 = 2.5Volume of new solution                           = 100 + 50 = 150 ml.NNaOH left =2.5150=0.0167NHence normality of the mixture obtained is 0.0167 N