👉 Iodisms are a type of chemical reaction that involves the formation of an alkali metal ion (e.g., Na+) from two non-metal ions (e.g., Ca2+ and Mg2+) at elevated temperatures. The reaction is named after the element iodine, which has the atomic number 12. The term "iodisms" is often used in the context of organic chemistry to describe a chemical reaction that involves the formation of an alkali metal ion from two non-metal ions