The formula unit for the ionic compound, strontium chloride, consists of which of the following?

? 1 Sr+ ion and 1 Cl- ion
? 2 Sr+ ions and 1 Cl2- ion
? 1 Sr2+ ion and 2 Cl- ions
? 1 Sr2+ ion and 1 Cl2- ion
? 1 Sr2- ion and 2 Cl+ ions

1 answer

The correct formula unit for the ionic compound strontium chloride consists of 1 Sr²⁺ ion and 2 Cl⁻ ions.

Strontium has a 2+ charge (Sr²⁺), and chloride has a 1- charge (Cl⁻). To balance the charges in the compound, you need two chloride ions for every strontium ion, which results in the formula SrCl₂.

So the answer is: 1 Sr²⁺ ion and 2 Cl⁻ ions.