Paul Lewing on sat 17 jul 04
Hi, Edouard. I read your article (another in an excellent series) on
antimony the other day. I have a question.
Do you know at what temperature antimony begins to volatilize? I know it's
pretty much gone by about cone 01. Does it volatilize under all conditions,
or does oxidation or reduction affect it? Does it matter what form the
antimony is in? Does it matter if it's fritted with something else?
Paul Lewing, Seattle
PS. Nice to see a picture of you and some of your work, as well.
Ivor and Olive Lewis on sun 18 jul 04
Dear Paul Lewig,
Kaye and Laby tell me that Antimony (Metal) has a boiling point of
1640=BA C. Antimony Trioxide melts at 655=BA C and boils at 1425=BA C.
Antimony Pentoxide is unstable. The Trioxide is reduced to the
metallic state when smelted with charcoal so you might infer that it
will be reduced by Carbon Monoxide.
The melting point of the oxide suggests it is most useful as a low
temperature melting agent. Isn't it used in the compounding of on
glaze enamels? What do the Hamers say in their most recent edition?
Best regards,
Ivor Lewis.
Redhill,
S. Australia.
daniel on wed 21 jul 04
Hi Ivor,
Just thought 'd answer the bit about what Hamer and Hamer say on this in
the new ed.
The citation does not quote a MP, though there is a table in the back which
quotes 650 C as the MP. There is no mention of a boiling point that I could
find. It does mention Naples Yellow from Lead Antimonate. The only reference
to volatility that I find is this "There is a tendency for antimony oxide to
volatilize at stoneware temperatures." They do state that it is a glass
former as well as an opacifier and modifier. They also mention that it is
poisonous.
The text does not answer Paul's questions I'm afraid.
> What do the Hamers say in their most recent edition?
Thanx
D
Belmont, California, USA
(ex terra australis)
Ivor and Olive Lewis on thu 22 jul 04
Dear Daniel,
Do Hamer and Hamer distinguish between the metallic state and the
oxide. If it is the oxide given in the table then this is an
approximate value, based on recognised collections of physical and
chemical data.Where do they get their information from. Is this given
in the bibliography?
Thanks for putting this information on the map.
Best regards,
Ivor Lewis.
Redhill,
S. Australia.
.
daniel on fri 23 jul 04
Hi Ivor,
They give antimony oxide with 650 C as the melting point, and antimonate of
lead with a MP of 800 C. The metal is briefly referred to in the citation
(no data on the MP for the metal in either the table or text) but only to
describe it as a semi-metal, leading to the description of the oxide as
possessing some metallic and some nonmetallic properties. They do not quote
a source for the MP data and the bibliography is not annotated. The only
specifically chemical/science texts that they mention are A. Isaacs et al,
Concise Science Dictionary and G.J. Leigh, Nomenclature of Inorganic
Chemistry.
Thanx
D
Belmont, California, USA
(ex terra australis)
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