Using the periodic table, predict the charge of the most stable ion of the following elements: (d) I

Key Concepts

Periodic Table and Group Trends

The periodic table organizes elements based on their atomic number and properties. Elements in the same group (column) exhibit similar chemical behaviors, including their tendency to gain or lose electrons. For example, halogens like iodine (I) are found in Group 17 and typically gain one electron to achieve a stable electron configuration, resulting in a charge of -1.

Ion Formation

Ions are charged particles formed when atoms gain or lose electrons. The charge of an ion reflects the difference between the number of protons and electrons. For iodine, which has seven valence electrons, it tends to gain one electron to complete its octet, forming a negatively charged ion (I⁻) that is more stable.

Stability of Ions

The stability of an ion is influenced by its electron configuration. Ions that achieve a noble gas configuration are generally more stable. For iodine, gaining an electron to form I⁻ allows it to mimic the electron configuration of xenon, a noble gas, thus enhancing its stability and making I⁻ the most stable ion for iodine.