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Name: Bohrium |
Boiling Point: unknown Melting Point: unknown Electrons Energy Level: 2, 8, 18, 32, 32, 13, 2 Isotopes: 16 + None Stable Heat of Vaporization: unknown Heat of Fusion: unknown Density: unknown Specific Heat: unknown Atomic Radius: unknown Ionic Radius: unknown Electronegativity: unknown Vapor Pressure: unknown |
1s2 2s2p6 3s2p6d10 4s2p6d10f14 5s2p6d10f14 6s2p6d5 7s2 |
Bohrium was synthesized in 1976 by a Soviet team led by Y. Oganessian at the Joint Institute for Nuclear Research at Dubna, Russia, who produced isotope 261Bh with a half-life of 1-2 ms (later data gave a half life of around 10 ms). They did this by bombarding bismuth-204 with heavy nuclei of chromium-54.
In 1981 a German research team led by Peter Armbruster and Gottfried Munzenberg at the Gesellschaft fur Schwerionenforschung (Institute for Heavy Ion Research) in Darmstadt were also able to confirm the Soviet team's results and produce bohrium, this time the longer-lived Bh-262.
The Germans suggested the name nielsbohrium with symbol Ns to honor the Danish physicist Niels Bohr. The Soviets had suggested this name be given to element 105 (dubnium).
Niels Bohr
There was an element naming controversy as to what the elements from 101 to 109 were to be called; thus IUPAC adopted unnilseptium, symbol Uns) as a temporary, systematic element name for this element. In 1994 a committee of IUPAC recommended that element 107 be named bohrium. While this conforms to the names of other elements honoring individuals, where only the surname is taken, it was opposed by many who were concerned that it could be confused with boron. Despite this, the name bohrium for element 107 was recognized internationally in 1997.
1s2 | |||||||
2s2 | 2p6 | ||||||
3s2 | 3p6 | 3d10 | |||||
4s2 | 4p6 | 4d10 | 4f14 | ||||
5s2 | 5p6 | 5d10 | 5f14 | ||||
6s2 | 6p6 | 6d5 | |||||
7s2 |
Bohrium is a synthetic element whose most stable isotope, Bh-267, has a half-life of 22 seconds.
Isotope | Atomic Mass | Half-Life |
---|---|---|
260Bh | 260.12197 | ~0.3 ms |
261Bh | 261.12166 | 13 ms |
262Bh | 262.12289 | 290 ms |
263Bh | 263.12304 | ~200 ms |
264Bh | 264.1246 | 1.3 seconds |
265Bh | 265.12515 | 0.9 seconds |
266Bh | 266.12694 | 5 seconds |
267Bh | 267.12765 | 22 seconds |
268Bh | 268.12976 | ~25 seconds |
269Bh | 269.13069 | ~25 seconds |
270Bh | 270.13362 | ~30 seconds |
271Bh | 271.13518 | ~40 seconds |
272Bh | 272.13803 | 10 seconds |
273Bh | 273.13962 | ~90 minutes |
274Bh | 274.14244 | ~90 minutes |
275Bh | 275.14425 | ~40 minutes |
Bohrium Data |
Atomic Structure
Chemical Properties
Physical Properties
Regulatory / Health
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Transition Metals | ||||||||||
Group | 3 (IIIB) |
4 (IVB) |
5 (VB) |
6 (VIB) |
7 (VIIB) |
8 (VIIIB) |
9 (VIIIB) |
10 (VIIIB) | 11 (IB) |
12 (IIB) |
Period 4 | 21 Sc 44.95 |
22 Ti 47.86 |
23 V 50.94 |
24 Cr 51.99 |
25 Mn 54.93 |
26 Fe 55.84 |
27 Co 58.93 |
28 Ni 58.69 |
29 Cu 63.54 |
30 Zn 65.39 |
Period 5 | 39 Y 88.90 |
40 Zr 91.22 |
41 Nb 92.90 |
42 Mo 95.94 |
43 Tc 98.00 |
44 Ru 101.0 |
45 Rh 102.9 |
46 Pd 106.4 |
47 Ag 107.8 |
48 Cd 112.4 |
Period 6 | 57 La 138.9 |
72 Hf 178.4 |
73 Ta 180.9 |
74 W 183.8 |
75 Re 186.2 |
76 Os 190.2 |
77 Ir 192.2 |
78 Pt 195.0 |
79 Au 196.9 |
80 Hg 200.5 |
Period 7 | 89 Ac 227.0 |
104 Rf 261.0 |
105 Db 262.0 |
106 Sg 266.0 |
107 Bh 264.0 |
108 Hs 269.0 |
109 Mt 268.0 |
110 Ds 269.0 |
111 Rg 272.0 |
112 Uub 277.0 |