* Heat and Molecular Motion: Heat energy causes molecules to move faster and spread out.

* Gas to Liquid: To change a gas to a liquid (condensation), you need to slow down the molecules and bring them closer together. This is achieved by:

* Lowering the temperature: This reduces the kinetic energy of the molecules, causing them to move slower.

* Increasing the pressure: This forces the molecules closer together, increasing their density.

Let me know if you have any other science questions!