Question

A 1.00 L sample of a gas has a mass of 1.92 g at STP. What is the molar mass (molecular weight) of the gas

Answer 1

To find the molar mass of a 1.00 L sample of a gas that has a mass of 1.92 g at STP, use the density of the gas and the fact that the molar volume of an ideal gas is 22.4 L at STP to calculate the molar mass, which is 43.01 g/mol.

Step-by-step explanation:

Calculating Molar Mass of a Gas at STP

To calculate the molar mass of a gas at STP (standard temperature and pressure), you can use the density of the gas along with the molar volume of an ideal gas at STP. When given a 1.00 L sample of a gas that has a mass of 1.92 g at STP, you can use this formula:

Molar mass (MM) = mass of the gas (g) / volume of the gas (L) × molar volume (L/mol)

At STP, 1 mole of any ideal gas occupies 22.4 L. Thus, the molar mass can be calculated using the volume and mass of the gas:

MM = 1.92 g / 1.00 L × 22.4 L/mol

MM = 1.92 g/L × 22.4 L/mol = 43.01 g/mol

Therefore, the molar mass of the gas is 43.01 g/mol.

Answer 2

The answer is below

Step-by-step explanation:

Avogadro stated that "Equal volumes of all gases at the same temperature and pressure contain the same number of molecules". Hence at standard temperature and pressure 1 mole of a gas occupies 22.4 liters of volume.

1 mol = 22.4 liters

Given a gas with 1 L and mass of 1.92 g at STP.

number of moles = 1 L / (22.4 L / mol) = 0.0446 mol

The molar mass = mass of gas / number of moles

molar mass = 1.92 g / 0.0446 mol

molar mass = 43.008 g / mol