Question

2 g of 109% oleum is diluted with water. To neutralize this solution completely, 44.49 ml of $Ca(OH{)}_2$ solution is required. What is the molarity of $Ca(OH{)}_2$ solution?

• A. 1.0 M
• B. 0.1 M
• C. 0.05 M
• D. 0.5 M

Answer 1

The correct option is D 0.5 M

2 g of 109% oleum $=2\times 1.09=2.18$ g of $H_{2}S{O}_4$ in dilute solution.
So, gm eq. of $H_{2}S{O}_4=\frac{2.18}{98}\times 2$
Similarly, gm eq. of $Ca(OH{)}_2=44.49\times {10}^{-3}\times M\times 2$
Since,
$gmeq.of{H}_{2}S{O}_4=gmeq.ofCa(OH{)}_2$
Therefore,
$\frac{2.18}{98}\times 2=44.49\times {10}^{-3}\times M\times 2$
$\Rightarrow M=0.5$