Hydriodic acid, also known as hydrogen iodide, is a strong acid that is commonly used in chemical reactions. Its chemical formula is HI, and it is a colorless liquid that is highly reactive. Some synonyms for hydriodic acid include iodane, iodine monohydride, and hydroiodic acid. It is an important reagent in the production of inorganic iodides and is used in various industries such as pharmaceuticals, electronics, and semiconductors. Hydriodic acid is also used in the preparation of organic compounds such as certain types of solvents and nitro compounds. Despite its many applications, it is a corrosive and toxic substance and must be handled with care.