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Bismuth is the chemical element with atomic number 83, symbol Bi. It is
the fifth and last element in the group of pnictogens (group No. 15). It is
toxic but less than lead which it therefore tends to replace for certain uses,
and it is not a trace element: it has no known physiological role. Reputed to be
very weakly present in animal organisms, its environmental kinetics and in
organisms has been little studied (unlike that of other nearby heavy metals).
It can theoretically be compared to phosphorus P, antimony Sb and arsenic As,
belonging to group 15, but also tin Sn and lead Pb belonging to group 14. The
successive elements of group 15 (nitrogen N, phosphorus P, arsenic As, antimony
Sb and bismuth) show an increasing tendency to form stable sulfides rather than
oxides: bismuth is clearly chalcophilic.
The simple bismuth body is a poor silvery white metal, with a shiny, hard and
brittle reddish reflection, of which all salts and vapors are toxic.
Its atomic electronic structure corresponds to [Xe] (4f) 14 (5d) 10 (6s) 2 (6p)
3. A donation or removal of electrons of the same quantum status, except for
spin, justifies the oxidation degrees +3 and +5, the first degree being much
more frequent in its compounds because the second is countered by the effect to
the inertia of the doublet s, combined with its remarkable spherical symmetry.
The ionic radius of the Bi3 + ion is around 1.2 Å and that of the Bi5 + ion is
reduced to 0.74 Å.
The rare simple body and its more common compounds (with sulfur and oxygen) were
if not described at least well known in practice by medieval miners in Western
Europe in search of lodes of chalcophilous, copper, lead-bearing, cobalt-bearing
minerals. or silver. The simple body was, even quite frequently in these mining
environments confined underground, present in the native state in the form of
native bismuth, it was distinguished from the native antimony with which it
would seem to have been frequently confused during the Antiquity to the point of
bearing its name in its root adapted from Arabic. Modern mining specialists
already know the reduction to air of bismuth. And since that time, it has
entered into the alloy composition [not clear].
he alloys based on Bi, Pb, Sn and still Cd have been known for more than a
century and a half for their fusibility and their density varying with
temperature. Bi2Sn2Pb melts around 94 กใ C, it expands from 0 กใ C to 35 กใ C,
contracts up to 55 กใ C at a lower volume than 0 กใ C, before expanding again from
55 กใ C to 'at the merger.
A Newtonian alloy melting around 94.5 กใ C was formerly defined by 8 parts by
mass of Bi, 5 of lead Pb and 5 of tin Sn. A Darcet alloy melting at 93 กใ C was
two by Bi, one by Pb and one by Sn. A Wood alloy melting at around 65 กใ C with 7
parts of Bi, 2 of Pb, 2 of Sn, and 2 of cadmium Cd.
The element is cited in the alloy in order of mass importance.
Albi
BiSb
BiCd
BiIn, BiInCd, BiInPbSn, BiInSn
BiPb, BiPbCd, BiPbCdIn, BiPbCdInSn, BiPbCdSn, BiPbIn, BiPbInSn, BiPbSn,
BiPbSnInCd, BiPbSnIn, BiPbSnCd, BiPbSnAg
BiTe in particle or powder
BiSn, BiSn to eutectic (song), BiSnCd, BiSnInPb, BiSnAg
InBi (fixed compound), InBi, InBiCd, InBiCdSn, InBiSn
PbBiSnCd
SnBiCuAg, SnBiZn
SnInAgBiCu
SnPbAgBi in particle or powder
SnAgBiCu
Wood metal in stick
copper aluminum lead Zinc tin nickel iron
magnesium bismuth manganese chromium cobalt titanium
Tungsten vanadium niobium indium molybdenum antimony
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