Question

A scientist has a container filled with carbon dioxide gas. The particles of this gas are far apart, moving quickly, and bouncing off the container walls. Then the particles slow down and collect at the bottom of the container, such that they are close together and vibrating in a rigid structure.

What caused this change?

Answer 1

Temperature.

Step-by-step explanation:

The gas particles movements directly depend on temperature.

Is temperature is changed, particles react to it. High temperature means high movement speed. Low temperature means low movement speed.

So, in this case, temperature falling down explains best this phenomenon.

Answer 2

Temperature went down