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Mixing of Gases


A rigid vessel is connected to four separate 2.00 liter gas cylinders. Each cylinder contains a separate, diatomic gas at room temperature.

When the gases are combined and held at room temperature, which of the following most accurately describes what happens in the reaction vessel?


All of the gases immediately diffuse, causing the kinetic energy of the substances to increase.


The heavier diatomic gases diffuse slower than the lighter diatomic gases, causing a heterogeneous mixture in the new system.


The rate of diffusion differs for each gas, but the overall kinetic energy of the system remains constant.


The lightest mass gas is unable to diffuse into the new system due to the increased pressure by the heavier gases, causing only three of the four gases to mix in the new container.