Sciencemadness Discussion Board

sodium iodate

ethan_c - 14-7-2006 at 11:12

I give you fair warning. This topic is started with a large amount of ignorance, and a small amount of k3wl-ish intentions.

I have a quandary.
On my last day of work, my boss tossed me an unopened container of sodium iodate, and told me that Fisher sent it by accident and he didn't want to bother to send it back, and he knows I'll take free stuff any day.
So. It's only 100g, but this is a chemical I have no experience with.
Is anyone in dire need of some? What interesting stuff can I do with it? (priority goes to the suggestion involving the biggest crater ;))
I understand it's a fairly potent oxidizer- normally, I acquire a particular chemical for a particular purpose, since my rather limited budget doesn't allow for frivolous spending.

I realize that this thread is rather pointless and self-serving (unless any of you need it…), but I'll appreciate responses…

guy - 14-7-2006 at 12:10

Do this!

woelen - 15-7-2006 at 12:05

Iodate ion is not that good an oxidizer. I have potassium iodate and mixed that with red P. This mix can burn, but only slowly, something like a KNO3/C mix. This is in very strong contrast with KIO4, or KClO4 used as oxidizer. With those, the mix with red P explodes on ignition. Not to speak of mixes with KBrO3 or KClO3. These are insanely sensitive and also explosive.

NaIO3 probably can be used to make a very interesting chemical, KICl4. Ideally, you use KIO3, but with NaIO3, together with KCl I also expect it to work. Only NaIO3 will not work, the compound NaICl4 cannot be crystallized, it decomposed to NaCl and ICl3 on drying. Have a look at this webpage.

http://woelen.scheikunde.net/science/chem/exps/KIO3+HCl/inde...

The compound KICl4 is a very energetic compound, which, when mixed with magnesium powder, can be ignited with water. The ignited mix gives purple clouds of iodine while "burning".

[Edited on 15-7-06 by woelen]

pantone159 - 15-7-2006 at 15:22

This will fail miserably in the 'crater' department, but might be interesting anyways...

First, the experiments I found specify K iodate, not Na. The Na salt might work as well, but I don't know. What I found were some 'clock' reactions that have delayed color changes.

I found these in B. Shakhashiri, Chemical Demonstrations, Vol 4, and L. Ford, Chemical Magic.

1 - The Landolt Iodine Clock: Oxidation of Bisulfite by Iodate
Procedure: Pour 100 mL of 0.10 M KIO3, 50 mL of 1% starch, and 100 mL of H2O into a 400 mL beaker. Pour 20 mL of 0.25 M NaHSO3 and 130 mL H2O into a 600 mL beaker. Pour the contents of the 400 mL beaker into the 600 mL beaker, and start counting. In about 10 seconds, the mixture will suddenly change from colorless to blue-black.

2 - Old Nassau Orange and Black: The Landolt Reaction with Mercury Indicator
Procedure: In a 250 mL beaker, combine 65 mL of 0.25 M NaHSO3 and 85 mL of 1% starch solution. In a 400 mL beaker, pour 150 mL of 0.01 M HgCl2. In a 600 mL beaker, combine 110 mL of 0.10 KIO3 and 40 mL H2O.
Pour the 250 mL beaker into the 400, then quickly pour this into the 600, and start counting. The mixture will remain colorless at first, but after several seconds a bright orange precipitate will form, and several seconds later the mixture will turn black.

3 - Oscillating Clock Reaction
Procedure: Prepare solutions as follows:
A - 3 mL conc H2SO4, 500 mL H2O, 21 g KIO3.
B - 180 mL 30% H2O2, 320 mL H2O.
C - 8 g malonic acid, 1.9 g Mn(II)SO4-2H2O, 500 mL H2O.
D - 2.5 g starch, 500 mL H2O.
Add sucessively, equal volumes of A,B,C to a 500 mL grad and stir. The mixture changes from colorless to yellow, and this change will oscillate. Now add a little bit of D to the mix, and the oscillation changes to colorless to yellow to blue. The oscillations continue for at least 15 minutes.

There are other variations on these as well.