Write the Lewis symbols for the ions in each ionic compound. c. CaI₂

Key Concepts

Lewis Symbols

Lewis symbols, or Lewis dot structures, represent the valence electrons of an atom as dots around the element's symbol. This notation helps visualize how atoms bond and interact in chemical compounds. For ions, the Lewis symbol indicates the loss or gain of electrons, showing the resulting charge on the ion.

Ionic Compounds

Ionic compounds are formed through the electrostatic attraction between positively charged cations and negatively charged anions. In the case of calcium iodide (CaI2), calcium (Ca) loses two electrons to become a Ca²⁺ cation, while each iodine (I) atom gains one electron to become I⁻ anions. The formula reflects the ratio of these ions in the compound.

Charge Balance in Ionic Compounds

In ionic compounds, the total positive charge must balance the total negative charge to achieve electrical neutrality. For CaI2, the two I⁻ ions (each with a -1 charge) balance the +2 charge of the Ca²⁺ ion. Understanding this charge balance is crucial for correctly writing the formulas and Lewis symbols for the ions involved.