Here's a breakdown:

* Arrangement:

* Solid: Molecules are tightly packed in a fixed, ordered arrangement.

* Liquid: Molecules are close together but can move around more freely, forming a less ordered structure.

* Gas: Molecules are far apart and move randomly with high kinetic energy.

* Movement:

* Solid: Molecules vibrate in place but don't move freely.

* Liquid: Molecules can move around and slide past each other.

* Gas: Molecules move very quickly and are constantly colliding with each other and the walls of their container.

The amount of energy a substance has also plays a role. More energy leads to greater molecular movement, which can cause a phase change from solid to liquid to gas.