# What are the products of the hydrolysis of ICl3?

I have learnt that interhalogens on hydrolysis give a halic acid derived from the smaller atom and an oxoacid derived from the larger atom. For example hydrolysis of $\ce{BrF5}$ would give me $\ce{HF}$ and $\ce{HBrO3}$.

Similarly the hydrolysis of $\ce{ICl3}$ should give me $\ce{HCl}$ and $\ce{HIO2}$ but my textbook says that $\ce{HIO2}$ is too unstable to be isolated. What then would be the products of the reaction?

• Guess it would disproportionate to $\ce{HIO3}$ and something on the other side. – Ivan Neretin Apr 1 '17 at 11:36
• This book mentions the reaction, however, I am unable to comprehend the paragraph that follows the given reaction. – Gaurang Tandon Jul 6 '18 at 8:13

$$\ce{3ICl3 + 6H2O → 9HCl + HI + 2HIO3}$$

Iodine(III) chloride react with water to produce hydrogen chloride, hydrogen iodide and iodic acid. The reaction is called Hydrolysis of iodine trichloride.(source)

The reaction is same as @xavier_fakerat noted in the comment section.

Something like this:

$$\ce{2 ICl3 + 3 H2O -> ICl + HIO3 + 5 HCl}$$

Source: Chemistry of Interhalogen Compounds (Page 16) By P. B. Saxena 2007

Screenshot (click image for larger variant)

• Strangely some suggest that HI is produced too, but I think it depends on reaction conditions note: $${3ICl3 + 6H2O → 9HCl + HI + 2HIO3}$$ but I favor the disproportionation reaction above – xavier_fakerat Apr 1 '17 at 11:51
• @NilayGosh So it depends on reaction conditions right? – xavier_fakerat Apr 1 '17 at 17:55
• Basically yes. Also various iodine species and other intermediates will form during the reaction course but they are unstable and disproportionates. The type of intermediates forming depens on reaction conditions and concentration of water. – Nilay Ghosh Apr 1 '17 at 18:16