Taking into account that
Normality of NaOH =N1=0.2115 N
Volume of NaOH =V1=27.31 ml
Normality of HCl =N2=x N
Volume of HC l=37.45 ml
We may proceed like this:
V1*N1=V2*N2 27.31*0.2115=37.45*x , x=0.1542 N=0.1542 M .
Concentration of HCl = 0.1542 moles/liter.
Hope this is good for you
