Talk:Colors of chemicals
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Anybody got an Idea how to format this page best? Wikipedia formatting is rather tediuos. In other wikis I know a table is simply made by writing ||...||!
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[edit] From PNA/Chemicals
- Colors of chemicals is written in schoolteacher form, has some format problems, and also has some factual errors as brought up on its talk page. Needs help. --Alex S 04:51, 17 Mar 2004 (UTC)
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- I agree to MGM but then the Titel of the article should be changed accordingly.FriedrichB 02:53, 3 November 2006 (UTC)
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Colors of common chemical compounds
[edit] hydrated ions
| name | formula | colour |
|---|---|---|
| alkali metals | M+ | none |
| alkaline earth metals | M2+ | none |
| scandium | Sc3+ | ?? |
| titan | TiO2+ | none |
| vanadate | VO43- | none |
name formula colour
- alkali metals M+ none
- alkaline earth metals M2+ none
- scandium Sc3+ ??
- titan TiO2+ none
- vanadate VO43- none
- vanadyl VO2+ yellow
- chrome(III) Cr3+ green
- chromate CrO,,4,, ^2-^ yellow
- dichromate Cr,,2,,O,,7,, ^2-^ orange
| name | formula | colour |
| alkali metals | M+ | none |
| alkaline earth metals | M2+ | none |
| scandium | Sc3+ | ?? |
| titan | TiO2+ | none |
| vanadate | VO43- | none |
| vanadyl | VO2+ | yellow |
| chrome(III) | Cr3+ | green |
| chromate | CrO,,4,, ^2-^ | yellow |
| dichromate | Cr,,2,,O,,7,, ^2-^ | orange |
| mangan(II) | Mn2+ | VERY light pink |
| permanganate | MnO,,4,, ^-^ | deep violet |
| manganate (VI) | MnO,,4,, ^2-^ | green |
| manganate (V) | MnO,,4,, ^3-^ | blue |
| iron(II) | Fe2+ | light green |
| iron(III) | Fe3+ | yellow/green/reddish |
| cobalt | Co2+ | light red |
| nickel | Ni2+ | green |
| copper | Cu ^2+^ | blue |
| copper-ammonia complex | [Cu(NH3)4]2+ | deep blue |
| Zinc | Zn2+ | none |
(to be continued)
[edit] Hydrated Salts
Some distinction should be made between the fact that most salts are colorless when anhydrous, and only take on color when H2O is introduced into the crystalline structure. I'm a little sketchy on the chemical reasons behind this, though, so someone with a bit more experience than I should work on it. Also, the salts table probably ought to be expanded - I can work on that. K1avg 15:33, 30 Apr 2005 (UTC)
[edit] Organic compounds
Shouldn't there be alot of organics here, too? I'll see if I can find a representitive list... Adqam 14:14, 16 December 2005 (UTC)
As far as I know, not many common organic compounds have vivid colors; color is rarely used to distinguish between organic compounds. --Thezookeeper 22:57, 28 December 2005 (UTC)
- Off the top of my head there's lycopene, which is responsable for the red colouring of tomatoes. I agree that there are not many; but would argue that the organics that are coloured are somewhat significant. Adqam 16:47, 4 January 2006 (UTC)
[edit] Other
What exactly do you mean by giving colors for potassium, sodium, and hydrogen gas? Potassium gives off a purple flame when BURNED and sodium gives off a yellow flame when BURNED, but the elements are not purple or yellow by any means. And hydrogen gas is pretty...colorless... --Thezookeeper 03:55, 12 December 2005 (UTC)
- There is already an article about flame coloration i.e. Flame_test. Therefore this one should concentrate on the dissolved ions shouldn't it? --KIce 12:44, 22 January 2006 (UTC)
[edit] Quantum mechanics
There are complications: cobalt chloride is pink or blue depending on the state of hydration (blue dry, pink with water) so it's used as a moisture indicator in silica gel... Zinc Oxide is white, but IIRC, at higher temperatures becomes yellow, returning to white as it cools, and Strictly speaking, the cuprammonium ion isn't a hydrated ion.. Malcolm Farmer 20:31, 31 Jul 2003 (UTC)
What is all this talk of electron clouds being big or small ? It doesn't make any sense to me :-( As far as I ever knew colour is caused by the difference in energy of atomic or molecular orbitals being in the region of visible light. Alkaline metals have white compounds because the energy levels are widely spaced and therfore correspond to UV. Transition metals have coloured compunds because the d orbital of the (N-1)th shell and the s orbital of the of the Nth shell are much closer together in energy and are therfore able to absorb visible light.Have I been taught wrong ? theresa knott 13:50, 2 Dec 2003 (UTC)
theresa, your comments sound detailed enough to have merit; it's a good question. the article leaves you inferring there must be some correlation between the wavelength (or half?) and the cloud radius/diameter, though not necessarily discrete. are we talking reflective effect, absorption/reemission, etc. kind of the heart of the issue, would be interesting to see it detailed. Chris Rodgers 07:34, 8 Apr 2004 (UTC)
- You're right that the color of a substance depends on the spacing of its orbitals. I have an incomplete sort of idea about how this is related to the size of the electron clouds.
- Why do we have orbitals in the first place? Why are electron energy levels quantized? They're quantized because they're confined to a very small space. The more you confine them, the broader the gaps between possible energy levels. The addition of an atom to a molecule increases the available space and reduces the confinement. --Smack (talk) 19:57, 11 Jan 2005 (UTC)
I see if I can help you guys out. Since I study chemistry. It's a subject I feel I can contribute to. --MGM 15:22, Apr 18, 2004 (UTC)
[edit] Am I getting anything wrong?
Or is the introduction really as stupid as it sounds to me?
SundarKanna 08:34, 26 December 2005 (UTC)
