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Jdurg
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Nah. I'm talking about the negatively charged ones. -ide denotes negative charge so lanthanide would be La-. 
\"A real fart is beefy, has a density greater than or equal to the air surrounding it, consists of the unmistakable scent of broccoli, and usually
requires wiping afterwards.\"
http://maddox.xmission.com. |
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12AX7
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chemrox: you mean alumium?  (No? Check history on it!)
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Antwain
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Right, I missed that joke completely. 
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pantone159
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Back to the lanthanoids/whatever...
How well do these make the double sulfate "alum" salts like M(I)Ln(III)[SO4]2-xH2O? Some of these varieties are listed in my CRC. I have some
lanthanon metals and oxides I could mess with, making some crystals might be fun. Of the ones I have, Pr/Nd/Dy sound like they have the nicest
colors.
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Sedit
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chloric1 mentioned a really good source for these rare earth chemicals although he suggested that they are not reagent grades keep in mind that oxides
that respectable dealers sell are very pure because they have to perform over and over every time the batch of glaze is mixed and the slightest
contamination of any ion will throw the color off sometimes drasticly. I am good freinds with someone that owns a ceramic store and they will tell you
that almost every thing they get is 99.999% purity certifyed. If you find a local place that sells the oxides for glazes it will be nothing to have
them special order chemicals for you. They are mom and pop organizations most of the time and all it would mean to them is more money in there
pocket
~Sedit
PS: Just goes to show I have an order for uranium oxide on the way... so they aint very picky at all
[Edited on 14-2-2009 by Sedit]
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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DerAlte
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I know I should nor disinter antique trivia, but Sedit reopened this thread… and I read it. So here goes:
Sauron wrote, way back:
| Quote: | Yes, I just found that as well. In this instance I think IUPAC is not serving chemistry well, but, there it is.
Their argument is that the -ide suffix should only be used to denote negative ions.
However, I am an old dog and resist new tricks. It is obvious that all of the traditional chemical names that contain such minor inconsistencies
cannot be resolved in such a fashion without creating chaos.
In any case Antwain's periodic chart is merely indulging in a current fashion, it is not incorrect, merely nontraditional. |
And
| Quote: | | LANTHANIDE has a long and illustrious history of usage, whereas lanthanoid is a four year old johnny come lately |
The suffix –oid comes from the Greek ‘eidos’ = form, meaning ‘of the same form’, ‘like’. Hence such words as ‘anthropoid’
=’man-like’, ‘arachnoid’ in biology, or ’cycloid’ in mathematics. This usage is ancient (circa 1600s).
The suffix –ide is AFAIK a chemical artifact coined at the time of (maybe by) Lavoisier, and used to indicate ‘a compound with’ ;eg,
‘hydride’, ‘oxide’, ‘peroxide’, dihydride’ etc. There is no necessity for a negative ion, many –ides are covalent.
On the traditional chemical basis a ‘lanthanide’ is a compound with lanthanum. Whereas ‘Lanthanoid’ means like lanthanum. Hence, on good
linguistic grounds, it is far preferable. My favorite chemist, Linus Pauling, also uses the term ‘Lanthanon’, to confuse further. This I find too
argonic! Like calling Helium a metal! Or there’s Boron, and Silicon…
And while we are on it, aluminum is, of course, correctly, aluminium, as the British have it. Soda --> Sodium; Magnesia --> Magnesium; so
Alumina --> Aluminium; because –ium denotes metal.
‘Aluminum’ is like spelling ‘night’ as ‘nite’, except the latter sounds the same – but lacks 700 years of tradition. And, Sauron, what
is more traditional than ‘Rare Earths’, even if they aren’t that rare?
Sedit wrote:
| Quote: | | I am good freinds with someone that owns a ceramic store and they will tell you that almost every thing they get is 99.999% purity certified
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Sheer BS, I’m afraid. You’d be lucky to get reagent grade anything.
Der Alte
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Sedit
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No BS you can see the certificates on many of the products that are sold.
Now Im not saying every thing that you will find is that pure but many...many things are.
Some are also just dug from the earth and sold as is also, so one will have to make an inquiry as to whats what.
Granted that they are not made for use in a lab some products are very pure indeed due to the need for consistancy in the glaze colors and more
important the ability of the fluxes used in the glazes. The slightest impuritys in some glaze fluxes will be the difference between a job well done or
a pile of molten crap on you 2000$ kiln.
Either way other then spliting hairs here it is still worth looking into and most places will be more then happy to special order rare materials for
you.
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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not_important
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For oxides used to colour glazes in particular, and to a certain extent the glass forming oxides or similar compounds, a reasonable degree of purity
is needed to get consistent effects. The major exception is manganese, as it is a strong colourant and generally isn't harmed by some iron..
Rare earths for ceramics often run from 99.5% to 99.999%, with the chief contaminates being the adjacent REE. An example is this supplier http://www.baotou-rareearth.com/nd.html
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DerAlte
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@not_important
I suspect the high quality RE's are only used for laser work. Nd is used for welder's goggles but I doubt purity had to be high for that.
@Sedit
Maybe - I am not a potter or glass expert. Certainly most of the chemicals cannot be relied on to be better than typical reagent grade, often nearer
technical which approximately means unknown, chemically.
Cetainly, as not_important says, MnO2 is very impure, often just mined pyrolusite.
Der Alte
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Sedit
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| Quote: | Originally posted by DerAlte
Certainly most of the chemicals cannot be relied on to be better than typical reagent grade, often nearer technical which approximately means unknown,
chemically.
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Yes just blindly realying on it being pure is not a good idea but you can get certification from the distributer giving the chemical composition of
substances. One thing about ceramic industry is the more common the material the less pure its going to be. Such as the MnO for instance or products
like Gerstley Borate which went out of production because the mine closed up IIRC. Common materials are just dug out of the ground and sold as is
based on the composition it came out as. Incidently I remeber the struggle people had trying to reproduce the formula for Gerstley Borate until
manufactures started reproducing the mixture.
But back on topic since what where looking for are rare earth materials and the ceramic, glass, and super conductor industrys are still running test
with them you can get high purity with little searching.I remeber while taking my classes we had giant bags of MnO and borates but a relativly small
jar of Barium carbonate that was 99.999% pure(Which they threw out and wouldnt let me have ).
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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