What is the chemical formula of calcium iodide once more?

The correct answer is calcium iodide is represented by the formula CaI2 because of the need to balance the charges between calcium (Ca) and iodine (I). Calcium is an alkaline earth metal that typically has a +2 charge when it forms ions. Iodine, on the other hand, is a halogen and typically has a -1 charge.

To create a neutral compound, two iodide ions are required to balance the +2 charge from one calcium ion. This means you need two iodide (I-) ions to surround one calcium ion (Ca2+), resulting in the formula CaI2. This formula indicates that one calcium ion is combined with two iodide ions, satisfying the requirement for charge neutrality in the compound.

This process of determining the chemical formula through charge balancing is crucial in chemistry, as it not only reflects the ratio of the elements present but also ensures that the final compound is stable.