Bismuth
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| General |
| Name, Symbol, Number | Bismuth, Bi, 83 |
| Chemical series | True metals |
| Group, Period, Block | 15 (VA), 6 , p |
| Density, Hardness | 9780 kg/m3, 2.25 |
| Appearance | lustrous
reddish white
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| Atomic Properties |
| Atomic weight | 208.98038 amu |
| Atomic radius (calc.) | 160 (143) pm |
| Covalent radius | 146 pm |
| van der Waals radius | no data |
| Electron configuration | [Xe]44f14 5d10 6s2 6p3 |
| e- 's per energy level | 2, 8, 18, 32, 18, 5 |
| Oxidation states (Oxide) | 3, 5 (mildly acidic) |
| Crystal structure | Rhombohedral |
| Physical Properties |
| State of matter | Solid |
| Melting point | 544.4 K (520.3 °F) |
| Boiling point | 1837 K (2847 °F) |
| Molar volume | 21.31 ×1010-3 m3/mol |
| Heat of vaporization | 104.8 kJ/mol |
| Heat of fusion | 11.3 kJ/mol |
| Vapor pressure | 0.000627 Pa at 544 K |
| Speed of sound | 1790 m/s at 293.15 K |
| Miscellaneous |
| Electronegativity | 2.02 (Pauling scale) |
| Specific heat capacity | 122 J/(kg×K) |
| Electrical conductivity | 0.867 106/m ohm |
| Thermal conductivity | 07.87 W/(m×K) |
| 1st ionization potential | 703 kJ/mol |
| 2nd ionization potential | 1610 kJ/mol |
| 3rd ionization potential | 2466 kJ/mol |
| 4th ionization potential | 4370 kJ/mol |
| 5th ionization potential | 5400 kJ/mol |
| 6th ionization potential | 8520 kJ/mol |
| Most Stable Isotopes |
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| SI units & STP are used except where noted. |
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Bismuth is a chemical element in the periodic table that has the symbol Bi and atomic number 83. This is heavy, brittle, white crystalline trivalent true metal that has a pink tinge and chemically resembles arsenic and antimony. Most diamagnetic of all metals, bismuth has the lowest thermal conductivity of all the elements except mercury. Lead-free bismuth compounds are used in cosmetics and in medical procedures.
Notable Characteristics
Before 2003, Bismuth was thought to be the heaviest stable element, however research at the Institut d'Astrophysique Spatiale in Orsay, France calculated the alpha emission half-life of the metal to be (1.9 +/- 0.2) × 1019 years (meaning it is not a stable element). It is a brittle metal with a pinkish hue with an iridescent tarnish. Among the heavy metalss, it is the heaviest and the only non-toxic. No other metal is more diamagnetic than bismuth, except mercury. This metal, which occurs in its native form, has a high electrical resistance and also has the highest Hall effect of any metal (that is, it has the greatest increase in electrical resistance when it is placed in a magnetic field). When heated in air bismuth burns with a blue flame and its oxide forms yellow fumes.
Applications
Bismuth oxychloride is extensively used in cosmetics and bismuth subnitrate and subcarbonate are used in medicine. Other uses;
"Bismanol" (MnBiBi) is a strong permanent magnet.
- Bismuth alloys have low-melting temperature and are widely used for fire detection and suppression system safety devices.
- Bismuth is used in producing malleable irons and is finding use as a catalyst for making acrylic fibers.
- Also used as a thermocouple material.
- A carrier for U-235 or U233 fuel in nuclear reactors.
- Bismuth has also been used in solders.
In the early
1990s, research began on the evaluation of bismuth as a nontoxic replacement for lead in such uses as
ceramic glazes,
fishing sinkers,
food processing equipment, free-machining brasses for plumbing applications, lubricating greases, and shot for
waterfowl hunting.
History
Bismuth (
German Weisse Masse meaning "white mass"; later
Wisuth and
Bisemutum) was confused in early times with
tin and
lead due to its resemblance to those elements. In
1753 Claude Geoffroy Junine showed that this metal is distinct from lead.
Occurrence
Bismuthinite and bismite are the most important
ores of bismuth.
Canada,
Bolivia,
Japan,
Mexico, and
Peru are major producers. Bismuth produced in the
United States is obtained as a by-product of
copper,
gold,
lead,
silver,
tin and especially lead ore processing. The average price for bismuth in 2000 was
US 3.50 per pound.
