The volumes of two HCl solutions A (0.5N) and B(0.1N) to be mixed for preparing 2 L of 0.2 NHCl are:

Options

A. 0.5 L of A+1.5 L of B
B. 1.5 L of A +0.5 L of B
C. 1L of A+ 1 L of B
D. 0.75 L of A+1.25 L of B

Answer

A

Explanation

Let x L of A and (2-x) L of B are mixed `((N_1V_1+N_2V_2)/(V_1+V_2))=N_3`
`0.5 xx x+0.1 (2-x)=0.2 xx 2 rArr (0.5 -0.1)x=0.4-0.2`
`0.4x=0.2 rArr x=0.5L rArr` 0.5 L of A and 1.5L of B should be mixed