Sodium oxalate on heating with conc. $H_2SO_4$ gives

In which of the following reactions,hydrogen is liberated?
$(i)$ $Al_{(s)} + HCl_{(aq)} \rightarrow$
$(ii)$ $Al_{(s)} + NaOH_{(aq)} \rightarrow$
$(iii)$ $NaBH_4 + I_2 \rightarrow$

Oxalic acid reacts with concentrated $H_2SO_4$ to produce a mixture of two gases. When this mixture is passed through caustic potash,one of the gases is absorbed. Which substance is formed by the absorption of the gas in caustic potash?

The order $H_2O < H_2O_2$ is correct for which of the following properties?

$H_2C_2O_4 \xrightarrow{\Delta } \text{gas } (A) + \text{gas } (B) + \text{liquid } (C)$.
$\text{Gas } (A) \text{ burns with a blue flame and is oxidised to gas } (B)$.
$\text{Gas } (A) + Cl_2 \to (D) \xrightarrow{NH_3, \Delta } (E)$.
$A, B, C \text{ and } E \text{ are}$

Correlate the items listed in Column $I$ with those listed in Column $II$. Find out as many correlations as you can.

Column $I$	Column $II$
$A$. Synthesis gas	$1$. $Na_2[Na_4(PO_3)_6]$
$B$. Dihydrogen	$2$. Oxidising agent
$C$. Heavy water	$3$. Softening of water
$D$. Calgon	$4$. Reducing agent
$E$. Hydrogen peroxide	$5$. Stoichiometric compounds of $s-$block elements
$F$. Salt like hydrides	$6$. Prolonged electrolysis of water
	$7$. $Zn + NaOH$
	$8$. $Zn + dil. H_2SO_4$
	$9$. Synthesis of methanol
	$10$. Mixture of $CO$ and $H_2$