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video How to make iodine from an Alkali metal iodide, hydrochloric acid and hydrogen peroxide.
Make iodine from an Alkali metal iodide, hydrochloric acid and hydrogen peroxide.
Warning: This reaction makes small amounts of chlorine gas and should be performed outside or in a fumehood.
Our previous iodine making video: http://www.youtube.com/watch?v=2F_kPXbi2D8
Simply get some potassium or sodium iodide and dissolve in a minimal amount of water. Then add an equal amount of concentrated hydrochloric acid. Check this new volume and measure out five times more 3%hydrogen peroxide. Mix together the two solutions and let stand for ten minutes. Filter the iodine.
You can then purify by vaporization and crystallization.
Warning: This reaction makes small amounts of chlorine gas and should be performed outside or in a fumehood.
Our previous iodine making video: http://www.youtube.com/watch?v=2F_kPXbi2D8
Simply get some potassium or sodium iodide and dissolve in a minimal amount of water. Then add an equal amount of concentrated hydrochloric acid. Check this new volume and measure out five times more 3%hydrogen peroxide. Mix together the two solutions and let stand for ten minutes. Filter the iodine.
You can then purify by vaporization and crystallization.
a sign your hydrochloric acid is contaminated is that if you mix it with hydrogen peroxide the peroxide will neutralise the acid and form chlorine gas, as well as also changing a redish orange.
these are often contaminants found inside pool muriatic acid or pool brand hydrochloric acid, and are not filterd out as they dont need to be. also use distilled water as it acts as normal water contaminants act as a catalyst to form chlorine gas in hydrochloric acid and hydrogen peroxide.
2NaI(aq) + 2HCl(aq) -----> 2I(s) + 2NaCl(aq) + H2(g)
I think this is correct.
then
NaI(aq) + HCl(aq) + 2H2O2(aq) -------> I(s) + NaCl(aq) + 4H2O(L)
Tell me if this is wrong, in fact I'm sure most of it is. I just don't think any Cl gas will be produced.
But wouldn't the Cl produced by the H2O2 + HCl be aqueous? Although the HCl is in excess wouldn't the reaction be:
H2O2(aq) + HCl(aq) -----> H2O(L) + O2(g) + Cl(aq)
Then the excess HCl would react with the H2O, and that reaction would go to equilibrium:
HCl(aq) + H2O(L) <------> HCl(aq) + H2O(L)
The HCl being the acid, "donates" a H atom (or proton) to the Hydrogen Peroxide to produce H2O, O2 gas and aqueous Chlorine ions.
I think the energy required to transform the Cl ions in the HCl to gaseous chlorine is far more than any amount produced in this reaction.(I think)
Also, free monoatomic chlorine can never exist in aqueos solution. Only chloride ions or molecular chlorine.
And hydrogen peroxide *CAN* oxidize chloride ions into chlorine under acidic conditions. The table of reduction/oxidation potentials pegs its power at 1.8 volts, while chlorine is 1.4 volts. Clearly it can oxidize chlorine.
In fact, this is a known danger in the electronic industry when copper/hydrochloric acid solutions are regenerated using hydrogen peroxide. Excessive addition by an inexperienced operator results in a surge of chlorine gas that poses an extreme danger to the workers. This is why those etching solutions are not use often, not because they don't work, but because a mistake can result in a fatality.
=)