Sciencemadness Discussion Board

Old Nassau Reaction Variation

bismuthate - 16-10-2014 at 17:58

So Halloween is coming up. A great reaction for Halloween is the Old Nassau Reaction also Know as the Halloween clock reaction.
http://www.youtube.com/watch?v=Tv6_IsdnaGg
So cutting to the point:
Mercury sucks. Who likes using mercury salts? They're a pain!
So why don't we use Bismuth nitrate and any alkaloid? (my tap water contains some so yours might too) It should work to the same effect as mercury salts.
I would try it myself but my lab is shut down.
am I missing anything or will this work?

Brain&Force - 16-10-2014 at 19:28

Well, someone would have to try it. The kinetics may vary immensely.

Jylliana92 - 24-10-2014 at 13:30

I'm wondering... what if I do the classic iodine clock reaction, with orange food coloring... so that the colorless solution will be orange. I'm sure the black starch complex is much stronger so you won't see the orange when it's black..

bismuthate - 24-10-2014 at 17:28

Yup the iodine starch complex is incredibly dark. You couldn't see the food coloring.

Brain&Force - 24-10-2014 at 18:11

The Old Nassau, though, "clocks" orange, then black. Similarly, the Briggs-Rauscher clocks brown, then black, then clear again.

Arcuritech - 24-10-2014 at 19:17

Quote: Originally posted by Jylliana92  
I'm wondering... what if I do the classic iodine clock reaction, with orange food coloring... so that the colorless solution will be orange. I'm sure the black starch complex is much stronger so you won't see the orange when it's black..


You would need an orange dye that won't react or form a complex with any of the many components of the iodine clock mixture.

Such an organic dye seems unlikely to exist on account of the fact that the strong colors in dyes usually originate from lots of double bonds which the iodine, iodate*, and thiosulfate could all react with.

Using a very finely powdered highly insoluble (likely inorganic) dye should solve this problem at the expense of the clarity of the start solution - the powdered suspension would render the otherwise clear solution a translucent orange, while the final solution should retain its black color.

*edit to add iodate

[Edited on 2014-10-25 by Arcuritech]