In which of the following reactions,$H_2$ is liberated?
$i$. $Al_{(s)} + HCl_{(aq)} \rightarrow$
$ii$. $Al_{(s)} + NaOH_{(aq)} \rightarrow$
$iii$. $B_2H_{6(g)} + H_2O_{(l)} \rightarrow$
$iv$. $F_{2(g)} + H_2O_{(l)} \rightarrow$

Match the correct option from Column $-A$ and Column $-B$.

Column $-A$	Column $-B$
$(1).$ Calgon	$(a).$ $D_2O$
$(2).$ Perhydrol	$(b).$ Zeolite
$(3).$ Heavy water	$(c).$ Sodium hexametaphosphate
$(4).$ Aluminosilicate	$(d).$ Commercial name of Hydrogen peroxide

Fill in the blanks:
$(1)$ Only $..........$ element of group $-6$ forms hydride.
$(2)$ $..........$ is used as a moderator in nuclear reactors.
$(3)$ The three-dimensional arrangement in ice occurs due to $..........$ bonding.
$(4)$ $..........$ method is used to obtain $H_2O_2$ from $2-$ethylanthraquinol.

$CuSO_4$ solution $+$ lime is called

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

Consider the following statements:
$I$. Atomic hydrogen is obtained by passing an electric arc through hydrogen gas.
$II$. Hydrogen gas does not reduce heated aluminum oxide.
$III$. Finely divided palladium absorbs a large volume of hydrogen gas.
$IV$. Pure nascent hydrogen is obtained by the reaction of $Na$ with $C_2H_5OH$.
Which of the above statements are correct?