catalystic rainbow

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mtg
Posts: 441
Joined: 15 Aug 2011, 10:48
Job Title: Lab Tech
School: NDSC
Suburb: west gippsland
State/Location: VIC

catalystic rainbow

Post by mtg »

Does anyone know the reaction using ammonium molybdate? I vaguely remember sodium acetate? and that's it, maybe H2O2 as well. You make up 2 measuring cylinders and then put the catalyst in one and it goes through the rainbow colours.
RosalieL
Posts: 184
Joined: 28 Jan 2021, 13:24
Job Title: Lab Assistant
School: MCS
State/Location: NSW

Re: catalystic rainbow

Post by RosalieL »

I'm not sure about that one. Depending on what you're wanting it for, this might be useful. Put about 50ml vinegar in a 500ml measuring cylinder, top it up to 500ml with tap water, keep adding universal indicator (stirring with a stirring rod) till its a fairly strong red and then add about a rounded teaspoon of washing soda. Stir it gently for a couple of seconds then let it sit and you will get a rainbow in your measuring cylinder.
mtg
Posts: 441
Joined: 15 Aug 2011, 10:48
Job Title: Lab Tech
School: NDSC
Suburb: west gippsland
State/Location: VIC

Re: catalystic rainbow

Post by mtg »

No that's the junior one. I found Rainbow reaction that goes through all the colours using KI, NaS2O3, CH3COOH and the catalyst is H2O2, but I dont know how to dilute the 35% to 40vol now. Great prac but I wanted the the other one.
RosalieL
Posts: 184
Joined: 28 Jan 2021, 13:24
Job Title: Lab Assistant
School: MCS
State/Location: NSW

Re: catalystic rainbow

Post by RosalieL »

Did you ever find the one you were looking for? It sounds great! I’d love the info if you found it.
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