111
 
Rg  
272.000000
Roentgenium

Name: Roentgenium (Unununium)
Symbol: Rg (Uuu)
Atomic Number: 111
AtomicWeight: 272.000000
Family: Transition Metals
CAS RN: 54386-24-2
Description: A synthetic element not present in nature, appearance unknown, probably metallic solid
State (25 ° C): Unknown (Synthetic)
Oxidation states:
Valence Electrons: 5f146d107s1

Boiling Point:  unknown
Melting Point:
unknown
Electrons Energy Level: unknown
Isotopes: 12 + 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

History

It was discovered by Peter Armbruster, Gottfried Münzenber and their team working at the Gesellschaft fur Schwerionenforschung (GSI) in Darmstadt, Germany on December 8, 1994.   Only three atoms of it were observed (all 272Rg), by the fusion of bismuth-209 and nickel-64 in a linear accelerator.  (Nickel was bombarded onto the bismuth target.)

The name roentgenium was accepted as a permanent name on November 1, 2004 in honor of Wilhelm Roentgen; before this date, the element was known under the temporary IUPAC systematic element name unununium, symbol Uuu).  Some research has referred to it as eka-gold.

The official baptism took place at GSI, on Friday November 17, 2006, in the presence of Annette Schavan, the Federal German Minister of Research.

Characteristics

One of the super-heavy atoms.  It is a synthetic transition element whose presence in Group 11 probably would appear as a heavy, solid, shiny metal.  Due to the inert pair effect, it should be colored like gold.

1s2
2s2 2p6
3s2 3p6 3d10
4s2 4p6 4d10 4f14
5s2 5p6 5d10 5f14
6s2 6p6 6d10
7s1

Isotopes

Twelve isotopes of roentgenium are known. The longest-lived of these is 280Rg which decays through alpha decay and has a half-life of 3.6 seconds.  The shortest-lived isotope is 272Rg which decays through alpha decay and has a half life of 2.0 ms.  The other known isotope, 279Rg, decays through alpha decay and has a half-life of 0.17 seconds.

atom.gif (700 bytes)

Isotope  
Atomic Mass
 
Half-Life
272Rg 272.15362 2.0 ms
273Rg 273.15368 ~5 ms
274Rg 274.15571 6.4 ms
275Rg 275.15614 ~10 ms
276Rg 276.15849 ~100 ms
277Rg 277.15952 ~1 seconds
278Rg 278.16160 ~1 seconds
279Rg 279.16247 0.17 seconds
280Rg 280.16447 3.6 seconds
281Rg 281.16537 ~1 minutes
282Rg 282.16749 ~4 minutes
283Rg 283.16842 ~10 minutes

atom.gif (700 bytes)

Roentgenium Data

 

Atomic Structure

  • Number of Electrons (with no charge): 111
  • Number of Neutrons (most common/stable nuclide): 161
  • Number of Protons: 111

Chemical Properties

  • No Chemical properties information is currently available.

Physical Properties

  • Atomic Mass Average: 272
  • Boiling Point:
  • Coefficient of Lineal Thermal Expansion/K-1: N/A
  • Conductivity:
    Electrical:
    Thermal:
  • Description:
    Synthetically produced radioactive super heavy element with an extremely short half life that does not occur in nature.

Regulatory / Health

  • Levels In Humans:
    Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
    • Blood/mg dm-3: nil
    • Bone/p.p.m: nil
    • Liver/p.p.m: nil
    • Muscle/p.p.m: nil
    • Daily Dietary Intake: nil
    • Total Mass In Avg. 70kg human: nil

Who / Where / When / How

  • Discoverer: S.Hofmann, V.Ninov, F.P.Heßberger, P.Armbruster, H.Folger, G.Münzenberg, H.J.Schött
  • Discovery Location: Darmstadt Germany
  • Discovery Year: 1994
  • Name Origin:
    Named for Wilhelm Conrad Roentgen who discovered X-rays in 1895.
  • Abundance:
    • Earth's Crust/p.p.m.: nil
    • Seawater/p.p.m.: nil
    • Atmosphere/p.p.m.: nil
    • Sun (Relative to H=1E12): N/A
  • Sources:
    Syntheticly produced element normally produced by fusing two lighter elements in a heavy ion accelerator.
  • Uses:
    Of research interest only.
  • Additional Notes:
    In August of 2003 the International Union of Pure and Applied Chemistry (IUPAC) announced the official naming of this element (source: IUPAC, Element 111 is named roentgenium.

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