What is the empirical formula of potassium chloride?

The empirical formula for potassium chloride is ##"KCl"##.

The empirical formula for a compound is the lowest whole number ratio of in one molecule or formula unit of the compound. The chemical formula for an ionic compound such as ##"KCl"## is always the same as its empirical formula.

We can determine the empirical formula for potassium chloride by using the charges on the ions. Potassium ions have a ##1+## charge, and the formula ##"K"^+"##, and chloride ions have a ##1-## charge, and the formula ##"Cl"^(-)"##. All empirical formulas have a of zero. So the ratios of the positive and negative ions must result in an overall charge of zero. In the case of potassium and chlorine, a ##1:1## ratio results in a net charge of zero. So the formula for potassium chloride is ##"KCl"##.

##"K"^++"Cl"^(-)####rarr####"KCl"##