OXIDATIONS WITH POTASSIUM I0DATE

Potassium iodate is a powerful oxidising agent, but the course of the reaction is governed by the conditions under which it is employed. The reaction between potassium iodate and reducing agents such as iodide ion or arsenic(III) oxide in solutions of moderate acidity (0.1-2.0M hydrochloric acid) stops at the stage when the iodate is reduced to iodine  

As already indicated, the first of these reactions is very useful for the generation of known amounts of iodine, and it also serves as the basis of a method for standardising solutions of acids (Section 10.110). 

With a more powerful reductant, e.g. titanium(III) chloride, the iodate is reduced to iodide  

In more strongly acid solutions (3-6M hydrochloric acid) reduction occurs to iodine monochloride, and it is under these conditions that it is most widely used.20 21 

In hydrochloric acid solution, iodine monochloride forms a stable complex ion with chloride ion  

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