Reef Chemistry Question of the Day #64 Lugol's Iodine

[Randy Holmes-Farley]

Reef Chemistry Question of the Day #64

The form(s) of iodine in Lugol's solution are:


A. Iodide (I^-)
B. Molecular iodine (I₂)
C. Iodate (IO₃^-)
D. Organoiodine
E. Iodide and iodate
F. Iodide and molecular iodine
G. Iodate, iodide, and molecular iodine

Good luck!















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[Steven@]

E. Iodide and iodate

 

[saltyhog]

I thought it was used in the past stop uptake of radioactive iodine because it had elemental iodine in it? I'll say F.

 

[Randy Holmes-Farley]

And the answer is....F. Iodide and molecular iodine

Lugol's contains both iodine (I₂) and potassium iodide. There is twice as much iodide (I^-) as I₂.

The iodide is added to help make the I₂ more soluble in water. It reacts with it to form the product I₃^-, which is water soluble.

This has more:

http://en.wikipedia.org/wiki/Lugol's_iodine

and

http://www.advancedaquarist.com/2003/3/chemistry