BeanyBoy
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List of common Light-Sensitive Reagents (those needeing amber bottles)
Hi,
After a long absence from amateur chemistry, I'm back. I sold all the lab equipment to buy records when I fell in love with Rock 'N Roll back about
1972, except for the H-tube electrolysis apparatus. I'm in re-acquisition mode. With a good start on apparatus, I'm now starting to re-acquire an
inventory of reagents.
I've searched the board, and Googled a bit too, but I can't find something resembling a list of light-sensitive reagents, those which should be stored
in amber bottles. I can find only onesie-twosie references to this-or-that reagent needing amber.
Realizing there may be no comprehensive list, I'd appreciate a pointer to whatever list that might be.
tia,
-the beaner
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garage chemist
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There is no such list as far as I know. When you buy a reagent that is light-sensitive, it always comes in an amber bottle, so you don't need to worry
about that. If you make a substance that might be light-sensitive you have to inform yourself first, but you'll of course do that always before you
make a new substance.
Common things that need light protection are:
-all ethers and other solvents that can form peroxides. All organic solvents, without exception, come in amber bottles when ordered from reputable
suppliers, even when its not necessary.
- halogenated solvents (all of them, especially chloroform, DCM and CCl4, but also tri- and perchloroethylene)
- silver salts (all of them, as far as I know).
- aqueous solutions of chlorine and bromine (they decompose to the hydrogen halide acid and oxygen in light)
- some sensitive or easily oxidisable organic molecules
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YT2095
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K3Fe(CN)6 (red prussiate of potash) is also light sensitive.
and Nitric Acid is another that should be out of the light.
[Edited on 16-3-2007 by YT2095]
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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garage chemist
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Only nitric acid over 68% concentration is light sensitive, I think. I've never seen azeotropic HNO3 becoming yellow.
Where did you read that ferricyanide is light sensitive? I've kept mine in a clear jar until now. On wikipedia, it says its solutions are light
sensitive. Is this true for the crystalline substance, too?
Oh, and alkyl iodides are also notoriously light sensitive.
Alkali iodides too, to a lesser degree- they are also easily oxidised by air and become yellow and brown if not stored properly.
[Edited on 16-3-2007 by garage chemist]
[Edited on 16-3-2007 by garage chemist]
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joeflsts
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| Quote: | Originally posted by garage chemist
Where did you read that ferricyanide is light sensitive? I've kept mine in a clear jar until now. On wikipedia, it says its solutions are light
sensitive. Is this true for the crystalline substance, too?
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The MSDS for Potassium Ferricyanide, in the storage section, states that the substance should be "protected from light". Merck also states that it
should be protected from light. "The Merck Index, 11th, p.1214"
Joe
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BeanyBoy
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Thanks All
Ok,
This was helpful. I think the only thing I have right now that needs to be in amber already is (Lugols, and some tincture of Iodine), and after it
drys, the gram of iodine from I extracted from some tincture...
I'll just check into light sensitivity with each new addition to the inventory as I acquire them...
Regards,
-the real beany boy
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garage chemist
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Iodine itself is not light sensitive of course, what do you think would happen with light? Its an element, it cant decompose.
The tincture of iodine is light sensitive though, for the same reason why bromine water is light sensitive.
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BeanyBoy
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| Quote: | Originally posted by garage chemist
Iodine itself is not light sensitive of course, what do you think would happen with light? Its an element, it cant decompose.
The tincture of iodine is light sensitive though, for the same reason why bromine water is light sensitive. |
Something's been making the rounds here in the Midsection; with a fever of a little over 103, I'm not sure I was thinking at all...
After a little time in the mini-sweat lodge, I feel better...
Whew!
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The_Davster
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I don't think that just because its what the suppliers ship it in is good reasoning. I recieved conc. HCl in a brown glass botttle and 70%HNO3 in a
clear bottle. It turned yellow some months later.
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