Question

A large flask is evacuated and weighed, filled with argon gas, and then reweighed. When reweighed, the flask is found to have gained 3.221 g. It is again evacuated and then filled with a gas of unknown molar mass. When reweighed, the flask is found to have gained 8.107 g. Part A To estimate the molar mass of the unknown gas based on the molar mass of argon, which assumptions should be made?

Answer 1

Answer:

The molar mass of the unknown gas is 100.4 g/mol

Explanation:

Step 1: Data given

Molar mass of argon = 39.95 g/mol

After filling with argon the flask gained 3.221 grams

After filling with an unknown gas, the flask gained 8.107 grams

Step 2: Calculate the molar mass of the unknown gas

The gas with the higher molar mass will have the higher density.

Ar - 3.224 g; molar mass = 39.95 g/mol

X = 8.102 g; molar mass = ??

Molar mass of the unknown gas = 8.102g X *(39.95 g/mol  / 3.224 g) = 100.4 g/mol

The molar mass of the unknown gas is 100.4 g/mol