A mixture of carbon dioxide and an unknown gas was allowed to effuse from a container. The carbon dioxide took 1.25 times as long to escape as the unknown gas. Which one could be the unknown gas? A) H₂ B) HCl C) SO₂ D) Cl₂ E) CO

Question

Quizplus · Accepted Answer

The rate of effusion of a gas is inversely proportional to the square root of its molar mass. Since the carbon dioxide took 1.25 times as long to effuse as the unknown gas, we can assume that its molar mass is 1.25 times greater than that of the unknown gas. The only gas in the list with a significantly different molar mass is CO, which has a molar mass of 28 g/mol compared to the others which have molar masses greater than 50 g/mol. Therefore, CO is the likely unknown gas.

A Mixture of Carbon Dioxide and an Unknown Gas Was