Question

The volumes of $1M$ $HCl$ and $5M$ $HCl$ to be mixed to get $2lit$ of $2M$ $HCl$ are:

• A. $1lit$ and $1lit$
• B. $1.5lit$ and $0.5lit$
• C. $1.25lit$ and $0.75lit$
• D. $1.33lit$ and $0.66lit$

Answer 1

The correct option is B $1.5lit$ and $0.5lit$

Thus, $n_1+n_2=n$ $v_1+v_2=v$

$x+5y=4$ and also $x+y=2$

On equating both equation we have,

$x+5y=4$ or $x=4-5y$

$x+y=2$

$\Rightarrow 4-5y+y=2$

$\Rightarrow 4-4y=2$

$\Rightarrow 2-2y=1$ or $y=\frac{1}{2}L$

thus, $x=2-y=2-\frac{1}{2}=1.5L$

thus, the solution volume should be

$V_1=1.5L$ of $1M$ $HCl$

$V_2=0.5L$ of $5M$ $HCl$