Correct order of boiling point $(BP)$ is:

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

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

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.

Match the items in Column-$I$ with the relevant item in Column-$II$.

Column-$I$	Column-$II$
$A$. Hydrogen peroxide is used as a	$1$. zeolite
$B$. Used in Calgon method	$2$. perhydrol
$C$. Permanent hardness of hard water is removed by	$3$. sodium hexametaphosphate
	$4$. propellant

Match the following columns:

Column-$I$	Column-$II$
$(i)$ Hydrogen peroxide	$(a)$ Used as air purifier in submarines
$(ii)$ Calcium sulphate hemihydrate	$(b)$ Used for water softening
$(iii)$ Potassium superoxide	$(c)$ Antiseptic
$(iv)$ Calgon	$(d)$ Plaster of Paris