Freezing water to make ice cubes is a physical change because the water molecules are simply changing from a liquid state to a solid state. The chemical composition of the water does not change, and the ice cubes can be melted back into liquid water by heating them.

Here are some of the key characteristics of a physical change:

* The substance does not change its chemical composition. This means that the atoms and molecules that make up the substance remain the same.

* The substance may change its physical state. This means that the substance may change from a solid to a liquid, a liquid to a gas, or a gas to a solid.

* The physical properties of the substance may change. This means that the substance may change its color, density, melting point, or boiling point.

In the case of freezing water to make ice cubes, the water molecules are simply changing from a liquid state to a solid state. The chemical composition of the water does not change, and the ice cubes can be melted back into liquid water by heating them. Therefore, freezing water to make ice cubes is a physical change.