How many moles of methane are required in the combustion reaction of methane to produce $22 \ g$ of $CO_{2(g)}$ (in $mol$)?

$A$ sample of a metal oxide has the formula $M_{0.83}O_{1.00}$. The metal $M$ can exist in two oxidation states,$+2$ and $+3$. In the sample of $M_{0.83}O_{1.00}$,the percentage of metal ions existing in the $+2$ oxidation state is $.........\%$ (nearest integer).

The mass of $BaCO_3$ produced when excess $CO_2$ is bubbled through a solution of $0.205 \ mol$ $Ba(OH)_2$ is ............ $g$.

Match the following and select the correct option:

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

What volume of $0.1 \, M \, HCl$ in $cm^3$ is required to react completely with $1 \, g$ of pure calcium carbonate $(CaCO_3)$?

The volume of oxygen at $STP$ required to burn $2.4 \,g$ of carbon completely is $.... \,L$