Two 112-L tanks are filled with gas at 330 K. One contains 5.00 mol of Kr, and the other contains 5.00 mol of O₂. Considering the assumptions of kinetic–molecular theory, rank the gases from low to high for each of the following properties. (b) Density (g/L)

Key Concepts

Kinetic-Molecular Theory

Kinetic-molecular theory explains the behavior of gases in terms of particles in constant motion. It posits that gas particles are far apart, move freely, and collide elastically. This theory helps in understanding properties like pressure, temperature, and volume, which are crucial for analyzing gas behavior in different conditions.

Density of Gases

Density is defined as mass per unit volume. For gases, density can be influenced by temperature and pressure. The ideal gas law (PV=nRT) can be rearranged to find density, showing that at constant temperature and pressure, the density of a gas is directly proportional to its molar mass. Thus, comparing densities of different gases requires knowledge of their molar masses.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is a critical factor in determining the density of gases, as heavier gases will generally have higher densities at the same temperature and pressure. For the gases in the question, comparing the molar masses of Kr and O2 will help rank their densities.