Volume of $4.4 \ g$ of $CO_2$ at $NTP$ is ............... $L$

At $STP$,$4.4 \ g$ of an unknown gas occupies a volume of $2.24 \ L$. What is the gas?

At $STP$,'$x$' $g$ of a metal hydrogen carbonate $(MHCO_3)$ (molar mass $84 \ g \ mol^{-1}$) on heating gives $CO_2$,which can completely react with $0.2 \ mol$ of $MOH$ (molar mass $40 \ g \ mol^{-1}$) to give $MHCO_3$. The value of '$x$' is

The density of $SO_2$ at $STP$ is ......... $g/L$.

What is the weight of oxygen required for the complete combustion of $2.8 \, kg$ of ethylene? (in $kg$)

What will be the amount of $MgCl_2$ produced when $17 \ g$ of $HCl$ is reacted with an excess of $MgO$ in the following reaction?
$MgO + 2HCl \longrightarrow MgCl_2 + H_2O$