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

Step 1: Given data

At STP, a mole of any gas occupies a volume of $22.4L$

$4.4g$ of a gas at STP occupies a volume of$2.24L$

Step 2: Calculating the number of moles of gas

Hence, the number of moles of gas,

$$\begin{gathered} =\frac{2.24}{22.4} \\ =0.1moles. \end{gathered}$$

Step 3: Evaluating molecular weight

$0.1$moles of a gas =$4.4g.$

A mole of a gas

$$\begin{gathered} =4.4\times \frac{1}{0.1} \\ =44g \end{gathered}$$

This is equal to the molecular weight of carbon dioxide ,

$$\begin{gathered} =12+2\times 16(C{O}_2) \\ =44g \end{gathered}$$

Thus, the molecular weight of gas is$44g/mol$. It is the molecular weight of ${\mathrm{CO}}_2$(Carbon dioxide) gas.