An unknown gas effuses 1.73 times faster than krypton.What is the molar mass of the gas?
A)28.0 g/mol
B)48.4 g/mol
C)110 g/mol
D)251 g/mol

Question

Quizplus · Accepted Answer

The rate of effusion of a gas is inversely proportional to the square root of its molar mass (Graham's law of effusion). If the unknown gas effuses 1.73 times faster than krypton (with a molar mass of approximately 83.8 g/mol), we can set up the equation: (Rate of unknown gas / Rate of krypton) = sqrt(Molar mass of krypton / Molar mass of unknown gas) = 1.73. Solving for the molar mass of the unknown gas gives approximately 28.0 g/mol.

An Unknown Gas Effuses 1