When iodate is in excess, part of iodate will be converted into iodine. [8] Can be used to prepare ionized alkyl halides.

Crystallization of iodic acid from acidic solution as orthorhombic α-HIO

3 in space group P212121. The structure consists of pyramid-shaped molecules linked by hydrogen bonds and intermolecular iodine-oxygen interactions. The I=O bond length is 1.81 Å, while the I-OH distance is 1.89 Å. [3][4][5] Several other polymorphs have been reported, including the orthorhombic γ form in space group Pbca[6] and the orthorhombic δ form in space group P212121. [7] All crystalline forms contain pyramidal molecules, hydrogen bonds, and I···O interactions, but in different arrangements.

Iodic acid can be produced by oxidation of iodine I2 with strong oxidants such as nitric acid HNO3, chlorine Cl2, chloric acid HClO3, or hydrogen peroxide H2O2,[2] for example:

{\displaystyle {\ce {I2 + 6 H2O + 5Cl2 = 2 HIO3 + 10 HCl}}}

Iodic acid is a white water-soluble solid with the chemical formula HIO3. Its robustness contrasts with the instability of chloric and bromic acids. Iodic acid is characterized by iodine in the +5 oxidation state and is one of the most stable oxyacids among the halogens. When heated, the sample dehydrates to form iodine pentoxide. On further heating, iodine pentoxide decomposes further to give a mixture of iodine, oxygen and subiodine oxides.

Iodate Acid (HIO3) Combined with Tetraethylammonium Bromide as a Catalyst for Selective and Accelerated Sulfonation Oxidation