$4.4 \ g$ of a gas at $STP$ occupies a volume of $2.24 \ L$. The gas can be:

The molarity of a $NaOH$ solution prepared by dissolving $4 \ g$ of it in $250 \ mL$ of water is: (in $M$)

At $S.T.P.$, the volume of $7.5 \ g$ of a gas is $5.6 \ L$. The gas is

What is the percentage atom economy when the formula weight of the desired product is $65 \text{ u}$ and the sum of the formula weights of all reactants is $130 \text{ u}$ (in $\%$)?

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?

$A$ metal exists as an oxide with formula $M_{0.96} O$. Metal $M$ can exist as $M^{2+}$ and $M^{3+}$ in its oxide $M_{0.96} O$. The percentage of $M^{3+}$ in the oxide is nearly: (in $\%$)