I was looking at a few videos online.

If you type in "top ten amazing chemistry videos" into google and click the first link (wired science), you'll see what I'm speaking of.

Well the thing is, I'm curious about the rxn in video # 6.

It was described as "mysterious rxn creates undulating brew". I thought that the rxn was a equillibrium rxn of some sort since the "mystery" of it is that it like the title suggests, undulates from blue-black to colorless all on it's own whilst heating. After the video ends, or you just fast foward since I got the point of the rxn after a few color changes, there are a few rxns like that suggested for viewing and one has this man actually saying what is used. I read the bottom of the page where I showed you how to go to and someone suggested it was a "iodine clock rxn". Problem with that is, yes it does look like that but when you look up videos on that site it shows just one color change. I only found 2 rxns that matched the one I saw for #6 and it's apparently called Briggs Rauscher Oscillating clock rxn.

I'm curious to know why that rxn which is similar to the iodine clock rxn but shifts from products to reactants all on it's own happens and why the iodine clock rxn only has a color change once. I assume it's something added to one rxn and not the other but from what I saw, there are actually a few ways to do the rxn...but do they lead to different results?

Oh and I think you would be interested in viewing the other 9 video's on that site. I thought they were fun to watch.

Thanks Dr.Bob

I didn't look at the video but from what you describe it is the iodine clock reaction. I've never done the iodine clock but I have seen it done and I have seen the chemistry (but I don't remember the chemistry very well). Anyway, from what I've seen and read, I understand that the number of times the iodine clock changes color from colorless to black to colorless etc is controlled by the amount AND concentratins of the reactants. I understand, also, that it takes a little time and patience to hit the right combinations. It usually wows grade school and high school students. Thanks for bringing this to my attention. I will look at it sometime but right now I'm packing to take a trip. This is a quick break for me.

Oh..Have fun Dr.Bob =D

To find information about the reaction you saw in video #6, "mysterious rxn creates undulating brew," you mentioned that you found it on the Wired Science website. Here's how you can find the video again:

1. Open your web browser and go to www.google.com.
2. In the search bar, type "top ten amazing chemistry videos" and hit enter.
3. Look for the search result that is related to Wired Science and click on it.
4. On the Wired Science website, find the list of videos and click on the one labeled as #6, "mysterious rxn creates undulating brew."

Now, regarding your questions about the reaction and the difference between the iodine clock reaction and the Briggs Rauscher oscillating clock reaction:

1. The reason why the reaction in video #6 shifts from products to reactants on its own is due to the presence of oscillating chemical reactions. These reactions involve multiple steps and intermediate species that result in periodic changes in concentration and color. The specific mechanism for this reaction can vary, but it often involves the formation and decay of certain reactive intermediates.

2. The iodine clock reaction, on the other hand, typically undergoes a single color change due to the reaction reaching a specific endpoint. This reaction is often used to demonstrate the concept of reaction rates and involves the reaction between iodine and a reducing agent, such as thiosulfate ions. The color change occurs when the reaction reaches a certain point, indicating that a specific reactant or product has been consumed or formed.

3. The Briggs Rauscher oscillating clock reaction is a different version of an oscillating chemical reaction that exhibits multiple color changes and shifts between reactants and products. This reaction involves the oxidation of iodine and the reduction of manganese(II) ions. The exact mechanism of the reaction is quite complex and includes multiple feedback loops that lead to the observed oscillations.

While both reactions involve iodine, the differences lie in the specific reagents and conditions used, leading to distinct reaction behaviors. There can be various ways to perform the reactions, resulting in different results.

If you're interested in watching more chemistry videos, you can explore the other nine videos on the Wired Science website that you mentioned. Enjoy your exploration of fascinating chemistry demonstrations!