rcfunker
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Chameleon colour change experiment
10mg KMnO4 (Potassium Permanganate) dissolved in 25ml of water , which was added to:
2g C12H22O11 (Sucrose - a type of sugar - any sugar will usually work)
3.3g NaOH (Sodium Hydroxide)
Both dissolved into 250ml of water.
I used a magnetic stir plate (with a magnetic stir bar - one without the other is pretty much useless and a waste of money and effort) to mix the
solutions quickly and evenly. You can use a stirring rod, or even mix it by swirling the liquid by hand, however this will not mix as evenly and the
effect will not be so magnificent.
This experiment can be scaled! - you can replicate it using more or less water+chemicals, provided the ratios remain roughly the same.
Adding more KMnO4 will make the yellow-red phase more prominent while the purple-green phase will be very dark and difficult to discern. Adding less
KMnO4 will make the purple-green phase much more visible, but the yellow-red phase will become very pale and may not turn red at all.
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gdflp
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What is the point of this thread? This is VERY common knowledge, and a demonstration almost every chemist will see at some point in college.
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MrHomeScientist
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Don't be so quick to demean. While this experiment is indeed a common thing, the last paragraph in the OP does at least provide some interesting
observations on effects of concentration. rcfunker is posting a report of an experiment complete with observations; not all threads must contain
problems to be solved.
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Brain&Force
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Why not try it with hydrogen peroxide as the reducing agent to see what effect, if any, the reducer has on the experiment?
[Edited on 31.3.2014 by Brain&Force]
At the end of the day, simulating atoms doesn't beat working with the real things...
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aga
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Nice one rcfunker !
Those chemicals are here right now, so i will try it.
Personally i wasn't in college, or doing chemistry back then.
[Edited on 31-3-2014 by aga]
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aga
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I feel you need reminding gdflp about stuff.
Not all of us were born all-knowing Gods.
Some of us have to work at it.
Personally i'm 47 now, and found my interest in Chemistry re-kindled about 3 weeks about, which makes it about 31 years ago that i studied any
chemistry at all.
Sure, i know roughly Zero about chemistry on any measurable scale compared to you, but there is one thing I do know :-
The instant you think you know it all, or a thing is too far beneath you to be bothered with, is the instant that you cease to learn anything new.
[Edited on 31-3-2014 by aga]
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gdflp
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I'm sorry if I sounded rude. My only point was that this has been posted on this and many other forums, and I wasn't quite sure what information this
was adding. Now that I reread it, the differences in the amount of potassium permanganate is interesting.
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Zephyr
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Quote: Originally posted by aga  | I feel you need reminding gdflp about stuff.
Not all of us were born all-knowing Gods.
Some of us have to work at it.
Personally i'm 47 now, and found my interest in Chemistry re-kindled about 3 weeks about, which makes it about 31 years ago that i studied any
chemistry at all.
Sure, i know roughly Zero about chemistry on any measurable scale compared to you, but there is one thing I do know :-
The instant you think you know it all, or a thing is too far beneath you to be bothered with, is the instant that you cease to learn anything new.
[Edited on 31-3-2014 by aga] |
While it is a interesting experiment, I think that some new information/observations are required to warrant the creation of a new thread,
This experiment has been discussed i detain multiple times on sciencemadness and multiple YouTube videos have been made of the reaction.
http://www.sciencemadness.org/talk/viewthread.php?tid=13902
https://www.sciencemadness.org/whisper/viewthread.php?tid=15...
http://www.cleanvideosearch.com/media/action/yt/watch?v=4_UG...
Sorry for the last link, I am at school and cannot access YouTube.
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aga
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Humility is the most impressive expression of an intelligent Mind.
Thank you for your expression gdflp.
Could anyone suggest what else to add to the reaction(s) to make them even more interesting ?
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aga
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AFAIK a thread that holds no interest gets no responses ?
It's a fundamental Law of Bulletin Board Systems.
Maybe it needs restating : If a post is not interesting, ignore it, unless you're drunk, in which case the thread starts and generally gets hijacked
by the drunkards, in which case it gets, er, well, er, different.
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Brain&Force
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Also the concentration of sodium hydroxide has a significant effect on the blue-green phase of the reaction. Manganate is not stable in anything that
isn't extremely basic.
Is there a manganate(V) species that exists during the reduction?
At the end of the day, simulating atoms doesn't beat working with the real things...
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Fantasma4500
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if you scale this up to 45L and use 0.3g KMnO4 in total you will see a blue colour appear aswell, but this part is quickly over
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blogfast25
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If you rummage through the very long sticky 'permanganates thread' you'll find experimental claims to a 'hypomanganate V', if I recall well. Blue,
again IIRW...
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Fantasma4500
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well here is my reference
http://puu.sh/7TwIu.jpg
this is from my own video, one of the first parts of the reaction, as stated above it is a rather quick part of the reaction, so it could seem that it
is quite unstable
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