Question

Hydrochloric acid solutions $A$ and $B$ have concentration of $0.5 N$ and $0.1 N$ respectively. The volume of solutions $A$ and $B$ required to make $2$ litres of $0.2 N$ hydrochloric are

• A. $0.5 \,L \,of\, A + 1.5\, L\, of\, B$
• B. $1.5\, L \,of\, A \,+\, 0.5\, L\, of\, B$
• C. $1.0\, L\, of\, A\, + 1.0\, L\, of\, B$
• D. $0.75\, L\, of\, A \,+\, 1.25\, L\, of\, B$

Answer 1

Answer: (A)

$NV=N_{1}V_{1}+N_{2}V_{2}$
$0.2\times2=0.5x+0.1\left(2-x\right)$
$0.4=0.5x+0.2-0.1x$
$0.2=0.4x$
$x=\frac{1}{2}L=0.5L$