Which of the following samples will have the lowest pressure if they are all at the same temperature and in identical containers (same volume)? A) 15 g F₂ B) 15 g CO C) 15 g Kr D) 15 g CO₂ E) All of these samples will have the same pressure.

Question

Quizplus · Accepted Answer

The pressure of a gas in a container at a constant temperature and volume is directly proportional to the number of moles of the gas (according to the Ideal Gas Law, PV = nRT). Since all samples have the same mass and are in identical conditions, the sample with the highest molar mass will have the lowest number of moles and, consequently, the lowest pressure. Among the given options, Kr (Krypton) is a noble gas with a relatively high molar mass compared to the molecular masses of the compounds and elements listed, thus it will have the lowest number of moles and the lowest pressure.

Which of the Following Samples Will Have the Lowest Pressure