What is the volume of oxygen required for complete combustion of $0.25 \ mole$ of methane at $\text{S.T.P.}$ (in $dm^3$)?

The decomposition of $CaCO_3$ produces $11.2 \, dm^3$ of $CO_2$ gas at $STP$. What mass of $KOH$ in grams is required to completely neutralize this gas?

What products are formed when $1 \ mol$ of magnesium nitride is reacted with excess water?

The volume of water to be added to $100 \, cm^3$ of $0.5 \, N \, H_2SO_4$ to get decinormal concentration is ........ $cm^3$.

Match the following and select the correct option:

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

For per gram of reactant,the maximum quantity of $N_2$ gas is produced in which of the following thermal decomposition reactions? (Given: Atomic wt. : $Cr = 52 \ u, Ba = 137 \ u$).