When iodine is added to water, the following reaction results: I 2 (l) + H 2 - (aq) + 2H + (aq) + I - (aq). I 2 molecules and water molecules react to substances such as hypoiodite (OI -).The reaction can move both ways of the equilibrium, depending on the pH of the solution. Iodine may also occur as I 3 - (aq), HIO(aq), IO - (aq) en HIO 3 (aq). Iodine can bind to many different substances, for example other halogens.The compounds that are form behave differently when they come in contact with water. Solubility of iodine and iodine compounds. Water solubility of iodine is determined by temperature (20 o C) and pressure (1 bar), and is relatively low.odine is naturally present in water. The average concentration in seawater is about 60 ppb, but varies from place to place. Rivers usually contain about 5 ppb of iodine, and in mineral sources some ppm can even be found.