Using the periodic table to guide you, predict the chemical formula and name of the compound formed by the following elements: (c) Al and I

Verified step by step guidance

1. Identify the charges of the ions formed by each element. Aluminum (Al) typically forms a cation with a charge of +3, denoted as Al^{3+}. Iodine (I) typically forms an anion with a charge of -1, denoted as I^{-}.
2. Determine the ratio of ions needed to balance the charges. Since Al has a +3 charge and I has a -1 charge, you will need three iodide ions to balance one aluminum ion, resulting in a neutral compound.
3. Write the chemical formula by combining the ions in the ratio determined. The formula will be AlI_3, indicating one aluminum ion and three iodide ions.
4. Name the compound. The cation (Al) is named first, followed by the anion (I). The name of the compound is aluminum iodide.
5. Review the periodic table to confirm the typical charges of the ions and ensure the formula and name are consistent with standard chemical nomenclature.

Key Concepts

Ionic Bonding

Ionic bonding occurs when atoms transfer electrons to achieve full outer electron shells, resulting in the formation of charged ions. In this case, aluminum (Al) loses three electrons to become Al³⁺, while iodine (I) gains one electron to become I⁻. The electrostatic attraction between these oppositely charged ions leads to the formation of an ionic compound.

Chemical Formula

A chemical formula represents the types and numbers of atoms in a compound. For ionic compounds, the formula is determined by the ratio of the ions that balance the overall charge. In the case of aluminum and iodine, the formula is AlI₃, indicating that one aluminum ion combines with three iodide ions to achieve charge neutrality.

Naming Ionic Compounds

The naming of ionic compounds follows specific conventions. The cation (positive ion) is named first, followed by the anion (negative ion). For the compound formed by aluminum and iodine, the name is aluminum iodide, where 'aluminum' refers to the Al³⁺ ion and 'iodide' refers to the I⁻ ion, reflecting the ionic nature of the compound.