Hydrolysis of peroxo-disulphuric acid $(H_2S_2O_8)$ gives

$12 \ V \ H_2O_2$ solution contains $680 \ g \ H_2O_2$. Then $\% \ W/V$ and volume of the solution is respectively ........ and ...........

The $pH$ of a solution of $H_2O_2$ is $6.0$. Some chlorine gas is bubbled into this solution. Which of the following is correct?

Predict the correct product when $Cl_2$ is passed through a $H^{18}O-^{18}OH$ solution.

Based on the given reaction scheme,identify which of the following statements is $CORRECT$?
$C + A \rightarrow B_2H_6 + B + H_2$
$B_2H_6 + NaH \rightarrow C$
$A + Na_2S_2O_3 \rightarrow B + Na_2S_4O_6$

The product$(s)$ formed when $H_2O_2$ reacts with disodium hydrogen phosphate is