Question

a HIO + b OH- <=> HIO3 + b H2O + b I^–. What are the values of a and b respectively in the above equation?

(a) 1, 2

(b) 1, 3

(c) 3, 2

(d) 3, 1

I have been asked this question in an international level competition.

I need to ask this question from Iodine, Bromine and Ozone Treatment in chapter Properties of Disinfection of Environmental Engineering

Answer 1

The correct answer is (c) 3, 2

Easiest explanation: 3HIO + 2OH^– <=> HIO3 + 2 H2O + 2 I^–. This equation is formed when the pH is above 8 and where decomposition of hypoiodite ion takes place.