# 20ml of 0.2M $Al_2(sO_4)_3$ is mixed with 20ml of 0.6M $BaCl_2$.Calculate the concentration of each ion in solution.

$\begin{array}{1 1}(a)\;0.2M\;Al^{+3},0.6M\;Cl^{-1}\\(b)\;0.1M\;Al^{+3},0.2M\;Cl^{-1}\\(c)\;0.3M\;Al^{+3},0.2M\;Cl^{-1}\\(d)\;0.2M\;Al^{+3},0.03M\;Cl^{-1}\end{array}$

$Al_2(SO_4)_3+BaCl_2\rightarrow BaSO_4+AlCl_3$
Meq =$N\times V$in ml =$M\times valency\times$V in ml
$Al^{3+}=\large\frac{24}{40\times 3}$
$\Rightarrow 0.2m$
$Cl^{-1}=\large\frac{24}{20}$
$\Rightarrow 0.6m$
Hence (a) is the correct answer.