Bismuth is a chemical element wi seembol Bi an atomic nummer 83. Bismuth, a pentavalent puir metal , chemically resembles arsenic an antimony . Elemental bismuth mey occur naiturally, tho its sulfide an oxide furm important commercial ores. The free element is 86% sae dense as leid . It is a brickle metal wi a siller white colour whan freshly produced, but is aften seen in air wi a pink tinge awin tae surface oxidation . Bismuth is the maist naiturally diamagnetic element an haes ane o the lawest values o thermal conductivity oot o aw metals.
Quick Facts Pronunciation, Appearance ...
Bismuth, 83 Bi Bismuth Pronunciation (BIZ -məth ) Appearance lustrous brownish silver Standard atomic weight A r, std (Bi)7002208980400000000♠ 208.98040 (1)[1] Bismuth in the periodic cairt
Atomic nummer (Z ) 83 Group group 15 (pnictogens) Period period 6 Block p-block Element category Post-transeetion metal Electron confeeguration [ Xe ] 4f14 5d10 6s2 6p3 Electrons per shell 2, 8, 18, 32, 18, 5 Pheesical properties Phase at STP solid Meltin pynt 544.7 K (271.5 °C, 520.7 °F) Bylin pynt 1837 K (1564 °C, 2847 °F) Density (near r.t. ) 9.78 g/cm3 when liquid (at m.p. ) 10.05 g/cm3 Heat o fusion 11.30 kJ/mol Heat o vapourisation 179 kJ/mol Molar heat capacity 25.52 J/(mol·K) Vapour pressur
P (Pa)
1
10
100
1 k
10 k
100 k
at T (K)
941
1041
1165
1325
1538
1835
Atomic properties Oxidation states −3, −2, −1, +1, +2, +3 , +4, +5 (a mildly acidic oxide) Electronegativity Pauling scale: 2.02 Ionisation energies 1st: 703 kJ/mol 2nd: 1610 kJ/mol 3rd: 2466 kJ/mol (more ) Atomic radius empirical: 156 pm Covalent radius 148±4 pm Van der Waals radius 207 pm Colour lines in a spectral range Spectral lines o bismuthIther properties Naitural occurrence primordial Creestal structur rhombohedral [2] Speed o soond thin rod 1790 m/s (at 20 °C) Thermal expansion 13.4 µm/(m·K) (at 25 °C) Thermal conductivity 7.97 W/(m·K) Electrical resistivity 1.29 µΩ·m (at 20 °C) Magnetic orderin diamagnetic Magnetic susceptibility − 280.1·10−6 cm3 /mol[3] Young's modulus 32 GPa Shear modulus 12 GPa Bulk modulus 31 GPa Poisson ratio 0.33 Mohs haurdness 2.25 Brinell haurdness 70–95 MPa CAS Nummer 7440-69-9 History Diskivery Claude François Geoffroy (1753)Main isotopes o bismuth
Iso tope
Abun dance
Hauf-life (t 1/2 )
Decay mode
Pro duct
207 Bi
syn
31.55 y
β+
207 Pb
208 Bi
syn
3.68×105 y
β+
208 Pb
209 Bi
100%
1.9×1019 y
α
205 Tl
210 Bi
trace
5.012 d
β−
210 Po
α
206 Tl
210m Bi
syn
3.04×106 y
IT
210 Bi
α
206 Tl
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