Sciencemadness Discussion Board

BZ reaction problem

spirocycle - 16-12-2010 at 07:12

I followed the procedure to make the stock solutions explained in the attached document, and tried a couple recipes, namely the last one on the list.
It didnt work at all, the ferroin stayed red the whole time.
I tried it again with less water, and then it stayed blue the whole time.
I tried with an intermediate amount of water, and it barely changed back and forth but with none of the beautiful patterns expected.

I tried another recipe that included some bromide initially, and I got what appeared to be iron filings precipitate out, and bubbles of what smelled like bromine produced.

does anyone have any experience with this reaction?
do the solutions need to be added in a specific order?
is there another, better recipe to use?

just to clarify, I'm using bromate/bromide and malonic acid

watson.fawkes - 16-12-2010 at 07:43

Quote: Originally posted by spirocycle  
I followed the procedure to make the stock solutions explained in the attached document
As of this reply, there's no attached document and no explanation of the acronym "BZ", and I have no idea what reaction you're talking about.

ScienceSquirrel - 16-12-2010 at 07:47

It is the Belousov-Zhabotinsky reaction, understandably called the BZ reaction as it hardly rolls off the tongue unless you are Eastern European! :D

http://en.wikipedia.org/wiki/Belousov%E2%80%93Zhabotinsky_re...

DDTea - 16-12-2010 at 08:58

I thought he was referring to Agent Buzz for a minute (3-quinuclidinyl benzilate).

not_important - 16-12-2010 at 17:35

Haven't ever seen a preferred sequence of mixing, except that ferroin is added last, after the bromine colour has faded. One reference is http://www.chemie.uni-regensburg.de/Organische_Chemie/Didakt...

spirocycle - 16-12-2010 at 20:41

Sorry about the lack of paper, I didnt check to make sure the upload worked correctly, and the file is 4mb so it wont attach


it can be found here: http://pubs.acs.org/doi/abs/10.1021/ed068p320

The WiZard is In - 17-12-2010 at 15:06

Quote: Originally posted by spirocycle  
I followed the procedure to make the stock solutions explained in the attached document, and tried a couple recipes, namely the last one on the list.



Next time your wander into the building with all the books
arranged horizontally ... if you have stack access pluck it off
the shelf or speak kindly upon a librarian and eye ball :—

Bassam Z. Shadhashiri
Chemical Demonstrations for Teachers of Chemistry
U of Wisconsin Press 1985

Volume 2 - Classic BZ and 4 modified procedures.

spirocycle - 17-12-2010 at 16:39

I've read that book, but the procedure explained is for the color changing solution.
I'm doing more of this:
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