The active mass of $64 \ g$ of $HI$ in a $2 \ L$ flask is......

Match the following items in List-$I$ with the corresponding results in List-$II$ (at $STP$):

List-$I$	List-$II$ (At $STP$)
$(A)$ $10 \ g \ CaCO_3 \xrightarrow{\Delta} \text{decomposition}$	$(i)$ $0.224 \ L \ CO_2$
$(B)$ $1.06 \ g \ Na_2CO_3 \xrightarrow{\text{Excess } HCl} \text{reaction}$	$(ii)$ $4.48 \ L \ CO_2$
$(C)$ $2.4 \ g \ C \xrightarrow{\text{Excess } O_2} \text{combustion}$	$(iii)$ $0.448 \ L \ CO_2$
$(D)$ $0.56 \ g \ CO \xrightarrow{\text{Excess } O_2} \text{combustion}$	$(iv)$ $2.24 \ L \ CO_2$
	$(v)$ $22.4 \ L \ CO_2$

What is the volume in $dm^3$ occupied by $3 \ mol$ of ammonia gas at $STP$?

If $0.2 \ mol$ of sulphuric acid is poured into $250 \ mL$ of water,calculate the concentration of the solution?

$1 \ mol$ of metal '$M$' reacts completely with alcohol to give $1.5 \ mol$ of $H_2$. What is the valency of metal '$M$'?

Magnetite can be reduced with $CO$ to yield iron metal and carbon dioxide. Calculate the mass of magnetite (in $kg$) needed to obtain $4 \ kg$ of iron if the process is $80 \%$ efficient. [Atomic weight of $Fe$ and $O$ are $56 \ g$ and $16 \ g$, respectively]