Write the correct ionic formula for the compound formed between each of the following pairs of ions: b. Ca²⁺ and S²⁻

Ionic compounds are formed when positively charged ions (cations) and negatively charged ions (anions) bond together through electrostatic forces. The overall charge of the compound must be neutral, meaning the total positive charge must balance the total negative charge. Understanding how to combine these ions based on their charges is essential for writing correct ionic formulas.

Charge balance is a fundamental principle in forming ionic compounds. Each ion has a specific charge, and when combining ions, the total positive charge from cations must equal the total negative charge from anions. For example, in the case of Ca²⁺ (with a +2 charge) and S²⁻ (with a -2 charge), one of each ion combines to create a neutral compound, CaS.

The chemical formula of an ionic compound represents the ratio of ions in the compound. It is written with the cation first followed by the anion, and subscripts indicate the number of each ion needed to achieve charge balance. For the compound formed from Ca²⁺ and S²⁻, the formula is CaS, indicating one calcium ion and one sulfide ion combine to form the compound.