Two gas jars are connected to each other, but they are separated by a closed valve. One gas jar contains oxygen, and the other contains hydrogen. What will happen when the valve is opened? (4 points)

Oxygen and hydrogen molecules will mix because of random movement of their molecules.

Oxygen and hydrogen molecules will remain in separate jars because of different partial pressures.

Oxygen and hydrogen molecules will remain in separate jars because of different rates of expansion.

Oxygen and hydrogen molecules will mix because the molecules have a much lower volume than the volume of the jars.