Here's why:

* Solid: Before melting, wax is a solid. It has a definite shape and volume.

* Liquid: When heated, the wax molecules gain energy and move further apart, breaking free from their rigid structure. This allows the wax to flow and take the shape of its container, making it a liquid.

It's important to remember that melting is a phase change, not a new state of matter. The wax itself remains the same chemical substance, just in a different physical form.