IIT/JEE Chemistry Practice #24: Molar Mass of a Gas

The video tutorial explains how to calculate the molar mass of a gas using the ideal gas law. It begins with a problem involving an evacuated glass vessel filled with a liquid and an ideal gas. The tutorial walks through basic calculations to determine the mass and volume of the liquid, then uses the ideal gas law to find the molar mass of the gas. Key steps include rearranging the ideal gas law equation and converting units to match the gas constant.

What is the initial mass of the evacuated glass vessel?

• 148.0 grams

• 0.5 grams

• 50.0 grams

• 98.0 grams

How do you calculate the volume of the liquid in the vessel?

• By multiplying the mass of the liquid by its density

• By subtracting the density from the mass of the liquid

• By dividing the mass of the liquid by its density

• By adding the mass of the liquid to its density

What is the formula for the ideal gas law?

• PV = RT

• P = nRT/V

• P = VnRT

• PV = nRT

What is the value of the gas constant R used in this context?

• 1.0 atm

• 8.314 J/mol K

• 0.0821 liters atmospheres per mole Kelvin

• 0.98 grams per milliliter

What is the calculated molar mass of the gas?

• 98 grams per mole

• 148 grams per mole

• 0.5 grams per mole

• 123 grams per mole