Rb - Rubidium

Rubidium was discovered spectroscopically in 1861 by Robert Bunsen and Kirchoff in Heidelberg, Germany.

Atomic number - 37 Density g/mL 1 .53
Atomic weight u 85 .4678 Melting point K 312 .64
Bonding radius A 2 .16 Boiling point K 961
Atomic radius A 2 .98 Heat of vaporization kJ/mol 72 .216
Ionization Potential V 4 .177 Heat of fusion kJ/mol 2 .192
Electronegativity - 0 .82 Specific heat J/gK 0 .363
The oxide is a strong base.
Crystal are body centered cubic.

Electron config. : [Kr] 5s1


Isotopes of Rb: Click mass number for decay process, product for element page.


074
64.9 msec
EC,10.400 MeV
Kr-74
73.944497
075
19.0 sec
EC,7.020 MeV
Kr-75
74.938571
076
36.5 sec
EC,8.500 MeV
Kr-76
75.935075
077
3.78 min
EC,5.344 MeV
Kr-77
76.930406
078
17.66 min
EC,7.224 MeV
Kr-78
77.928143
079
22.9 min
EC,3.649 MeV
Kr-79
78.924000
080
33.4 sec
EC,5.723 MeV
Kr-80
79.922522
081
4.576 hr
EC,2.237 MeV
Kr-81
80.918994
082
1.273 min
EC,4.400 MeV
Kr-82
81.918207
083
86.2 da
EC,4.000 MeV
Kr-83
82.915113
084
32.77 da
B-/EC,2.681
Sr-84/Kr-84
83.914387
085 72.165%

Stable

84.911792
086
18.631 da
B-/EC,1.775
Sr-86/Kr-86
85.911169
087 27.835%
4.75E10 yr
B-,4.800 MeV
Sr-87
86.909185
088
17.78 min
B-,5.316 MeV
Sr-88
87.911323
089
15.15 min
B-,4.501 MeV
Sr-89
88.912288
090
158 sec
B-,6.590 MeV
Sr-90
89.914813
091
58.4 sec
B-,5.861 MeV
Sr-91
90.916491
092
4.492 sec
B-/B-n,8.105
Sr-92/Sr-91
91.919683
093
5.84 sec
B-/B-n,7.462
Sr-93/Sr-92
92.922032
094
2.702 sec
B-/B-n,10.307
Sr-94/Sr-93
93.926430
095
377.5 msec
B-/B-n,9.279
Sr-95/Sr-94
94.929318
096
202.8 msec
B-/B-n,11.756
Sr-96/Sr-95
95.934270
097
169.9 msec
B-/B-n,10.420
Sr-97/Sr-96
96.937331
098
114 msec
B-/B-2n/B-n,12.344
Sr-98/Sr-96/Sr-97
97.941738
099
50.3 msec
B-/B-n,11.250
Sr-99/Sr-98
98.945324
100
51 msec
B-/B-n,13.500
Sr-100/Sr-99
99.949865
101
32 msec
B-/B-n,11.810
Sr-101/Sr-100
100.95319
102
37 msec
B-/B-n,2.500
Sr-102/Sr-101
102.0
MASS abund.
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass