The density of a certain gas is 1.98gdm _3 at stp. What is the molecular

Explanation

In this question, we are given the density of a gas at standard temperature and pressure (STP) and asked to find the molecular mass of the gas. We are also given the molar volume of a gas at STP, which is 22.4 dm\(^3\). To find the molecular mass, we can use the formula: \(Density = \frac{Molecular \: Mass}{Molar \: Volume}\) We can rearrange the formula to solve for molecular mass: \(Molecular \: Mass = Density \times Molar \: Volume\) Now, we can plug in the given density and molar volume values: \(Molecular \: Mass = 1.98 g/dm^3 \times 22.4 dm^3\) \(Molecular \: Mass = 44.352 g\) Since we need to find the molecular mass to a whole number, we can round it to the nearest whole number, which is 44 g. Therefore, the correct answer is Option A: 44 g.