Question

If 20 ml of 1M HCl solution is exactly neutralised by 10 ml of Ca (OH)2  solution, the strength of Ca(OH)2 in grams per litre of the solution is 
1) 37 2) 74 3)111 4)148 

Answer 1

normality of HCl = 1*molarity of HCl
                         = 1N
apply N1V1 = N2V2
1*20 = N2*10
N2 = 2
molarity of Ca(OH)2 = N2/2
                              = 2/2  = 1M
molarity = no.of moles/volume of solution in L
             = weight/(molecular weight*volume of solution in L)
1 = weight/(74*volume of solution in L)
74 = strength (in gram/L)
hence (2) option is correct