$10 \mathrm{g}$ sample of bleaching powder was dissolved into water to make the solution one litre. To this solution $35 \mathrm{mL}$ of $1.0\mathrm{M}$ Mohr salt solution was added containing enough ${\mathrm{H}}_2{\mathrm{SO}}_4.$ After the reaction was complete, the excess Mohr salt required $30 \mathrm{mL}$ of $0.1{\mathrm{MKMnO}}_4$ for oxidation. Find out the $\%$ of available ${\mathrm{Cl}}_2$ approximately is $(\mathrm{mol} \mathrm{wt}. 71).$

$20 \mathrm{mL}$ of a mixture of methane and a gaseous compound of Acetylene series were mixed with $100 \mathrm{mL}$ of oxygen and exploded. The volume of the products after cooling to original room temperature and pressure, was $80 \mathrm{mL}$ and on treatment with potash solution a further contracting of $40 \mathrm{mL}$. was observed. Calculate

(a) the molecular formula of the hydrocarbon,

(b) the percentage composition of the mixture.

One type of artificial diamond (commonly called $\mathrm{YAG}$ for yttrium aluminium garnet) can be represented by the formula ${\mathrm{Y}}_3{\mathrm{Al}}_5{\mathrm{O}}_{12}$.

(a) Calculate the weight percentage composition of this compound.

(b) What is the weight of yttrium present in a $200$ - carat $\mathrm{YAG}$ if $1$ carat $-200\mathrm{mg}? \left(\mathrm{Y}=89,\mathrm{Al}=27\right)$