Hydrogen iodide
Hydrogen iodide is a colorless diatomic gas with formula HI. It dissolves readily in water, forming hydroiodic acid.
Hydrogen halides: Binary compounds formed by hydrogen and a halogen, including hydrogen fluoride, hydrogen chloride, hydrogen bromide, and hydrogen iodide. HI is the hydrogen halide containing iodine.
Hydroiodination: The addition of hydrogen iodide across a carbon–carbon multiple bond. HI adds across unsaturated bonds to make organoiodine compounds.
Iodine: A halogen element with atomic number 53, commonly encountered as a dark, lustrous solid. Iodine is the larger atom bonded to hydrogen in HI.
Hydrogen fluoride: A hydrogen halide with formula HF that forms unusually strong hydrogen bonds. HF has a much stronger H–X bond and weaker acidity in water than HI.
Hydroiodic acid: The aqueous solution of hydrogen iodide, a strong acid and powerful reducing agent. Dissolving HI in water produces this strongly acidic solution.
Organoiodine compounds: Organic compounds containing at least one carbon–iodine bond. Hydroiodination and related HI reactions produce this broad family of compounds.
Hydrogen: The chemical element with atomic number 1, whose atoms form the H–I bond. Hydrogen supplies the proton and electron in the diatomic molecule.
Hydrogen chloride: A hydrogen halide gas with formula HCl that forms hydrochloric acid in water. HCl is a familiar neighboring hydrogen halide with a stronger H–X bond.
Acid dissociation constant: A quantitative measure of an acid's tendency to donate protons in solution. HI ionizes nearly completely in water, making its acid strength apparent.
Iodide: The anion I−, formed when hydrogen iodide donates a proton or gains an electron. HI supplies iodide ions used in synthesis and reduction.