Here's why:

* Compound: KBr is formed by the chemical combination of two different elements: potassium (K) and bromine (Br). This chemical combination results in a new substance with properties different from either potassium or bromine alone.

* Solid: At room temperature, KBr exists in a solid state. It has a defined shape and volume, and its particles are tightly packed together.

So, KBr is both a compound (due to its chemical composition) and a solid (due to its physical state at room temperature).