What is the empirical formula of potassium chloride?

1 Answer
Feb 6, 2016

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

Explanation:

The empirical formula for a compound is the lowest whole number ratio of elements 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 net charge 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"#