The statement "Solid potassium chloride composed of KCl molecules" is incorrect because potassium chloride (KCl) exists as an ionic compound, not as molecules.

Here's why:

* Ionic Compounds: KCl is formed by the electrostatic attraction between positively charged potassium ions (K+) and negatively charged chloride ions (Cl-). These ions are arranged in a crystal lattice structure, not as individual molecules.

* No Discrete Molecules: In ionic compounds, there are no discrete units like molecules where atoms are covalently bonded. Instead, there's a continuous repeating pattern of ions held together by strong electrostatic forces.

To be accurate, you should say:

* Solid potassium chloride is composed of a crystal lattice of potassium ions (K+) and chloride ions (Cl-)

Let me know if you have any other chemistry questions!