Rubidium

Rubidium (Rb)

Rubidium is the 37th element in the periodic table and has a symbol of Rb and atomic number of 37. It has an atomic weight of 85.4678 and a mass number of 85. Rubidium has thirty-seven protons and forty-eight neutrons in its nucleus, and thirty-seven electrons in five shells. It is located in group one, period five and block s of the periodic table. Soft silvery metallic element, belongs to group 1 of the periodic table. Rb-97, the naturally occurring isotope, is radioactive. It is highly reactive, with properties similar to other elements in group 1, like igniting spontaneously in air. Discovered spectroscopically in 1861 by W. Bunsen and G.R. Kirchoff.
Atomic Number37
Atomic Weight85.4678
Mass Number85
Group1
Period5
Blocks
Protons37 p+
Neutrons48 n0
Electrons37 e-
Animated Bohr Model of Rb (Rubidium)

Physical Properties

Atomic Radius
Molar Volume
Covalent Radius
Metallic Radius
Ionic Radius
Crystal Radius
Van der Waals Radius
Density
Atomic Radii of the Elements: Rubidium0102030405060708090100110120130140150160170180190200210220230240250260270280290300310pmAtomic RadiusCovalent RadiusMetallic RadiusVan der Waals Radius

Chemical Properties

Energy
Proton Affinity
Electron Affinity
Ionization Energy
Ionization Energies of Rb (Rubidium)
Heat of Vaporization
Heat of Fusion
Heat of Formation
Electrons
Electron Shells2, 8, 18, 8, 1
Bohr Model: Rb (Rubidium)
Valence Electrons1
Lewis Structure: Rb (Rubidium)
Electron Configuration[Kr] 5s1
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1
Enhanced Bohr Model of Rb (Rubidium)
Orbital Diagram of Rb (Rubidium)
Oxidation States-1, 1
Electronegativity
0.82
Electrophilicity Index
States of Matter
PhaseSolid
Gas Phase
Boiling Point
Melting Point
Critical Pressure
Critical Temperature
Triple Point
Visual

Rubidium is a Silver. Rb has a CPK of #ff1493, Jmol of #702eb0, and MOLCAS GV of #702eb0. The Appearance of Element 37 is grey white.

Color
Silver
Appearancegrey white
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
Molar Heat Capacity
Specific Heat Capacity
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
Electrical Resistivity
Superconducting Point
Magnetism
Typeparamagnetic
Magnetic Susceptibility (Mass)
0.0000000026 m³/Kg
Magnetic Susceptibility (Molar)
0.000000000222 m³/mol
Magnetic Susceptibility (Volume)
0.00000398
Magnetic Ordering
Curie Point
Neel Point
Structure

The Crystal Structure of Rubidium is BCC. The lattice constant of Rb is 5.59 Å. The lattice angles of Element 37 are π/2, π/2, π/2.

Crystal StructureBody Centered Cubic (BCC)
Lattice Constant
Lattice Anglesπ/2, π/2, π/2
Mechanical Properties

Rubidium has a Brinell of 0.216 MPa, and Mohs hardness of 0.3 MPa. The Bulk Modulus of Rb is 2.5 GPa. The Young Modulus of Element 37 is 2.4 GPa. The Speed of Sound of Rubidium (Rb) is 1300 m/s.

Hardness
Bulk Modulus
Shear Modulus
Young's Modulus
Poisson Ratio
Speed of Sound
Classification

The CAS Group of Rubidium is IA. The IUPAC Group of Rb is IA. The Glawe Number of Element 37 is 9. The Mendeleev Number of Rubidium (Rb) is 4. The Pettifor Number of Rubidium is 9. The Geochemical Class of Rb is alkali metal. The Goldschmidt Class of Element 37 is litophile.

CategoryAlkali metals, Alkali metals
CAS GroupIA
IUPAC GroupIA
Glawe Number9
Mendeleev Number4
Pettifor Number9
Geochemical Classalkali metal
Goldschmidt Classlitophile

Other

The Dipole Polarizability of Rubidium is 319.8 plus or minus 0.3 a₀. Rb has a C6 Dispersion Coefficient (CD) of 4769 a₀, and C6 Dispersion Coefficient (GB) of 4660 a₀. The Allotropes of Element 37 is . The Neutron Cross Section of Rubidium (Rb) is 0.38. The Neutron Mass Absorption of Rubidium is 0.0003. The Quantum Numbers of Rb is 2S1/2. The Space Group of Element 37 is 229 (Im_3m).

Gas Basicity
Dipole Polarizability
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
0.38
Neutron Mass Absorption
0.0003
Quantum Numbers2S1/2
Space Group229 (Im_3m)

Isotopes of Rubidium

Stable Isotopes1
Unstable Isotopes33
Natural Isotopes2
Isotopic Composition8572.17%8572.17%8727.83%8727.83%

71Rb

Mass Number71
Neutron Number34
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin5/2
Quadrupole Moment
Discovery Year
Parity-

Decay ModeIntensity
p (proton emission)

72Rb

Mass Number72
Neutron Number35
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
103 ± 22 ns
Spin1
Quadrupole Moment
Discovery Year2017
Parity+

Decay ModeIntensity
p (proton emission)

73Rb

Mass Number73
Neutron Number36
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin3/2
Quadrupole Moment
Discovery Year1996
Parity-

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)
p (proton emission)100%

74Rb

Mass Number74
Neutron Number37
Relative Atomic Mass
G-Factor
0
Abundance
Radioactivity☢️ Radioactive
Half Life
64.78 ± 0.03 ms
Spin0
Quadrupole Moment
0
Discovery Year1977
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)

75Rb

Mass Number75
Neutron Number38
Relative Atomic Mass
G-Factor
0.386 ± 0.00066666666666667
Abundance
Radioactivity☢️ Radioactive
Half Life
19 ± 1.2 s
Spin3/2
Quadrupole Moment
0.81 ± 0.04
Discovery Year1975
Parity-

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

76Rb

Mass Number76
Neutron Number39
Relative Atomic Mass
G-Factor
-0.372552 ± 0.000011
Abundance
Radioactivity☢️ Radioactive
Half Life
36.5 ± 0.6 s
Spin1
Quadrupole Moment
0.41 ± 0.09
Discovery Year1969
Parity-

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+α (β+-delayed α emission)3.8%

77Rb

Mass Number77
Neutron Number40
Relative Atomic Mass
G-Factor
0.43622666666667 ± 0.000013333333333333
Abundance
Radioactivity☢️ Radioactive
Half Life
3.78 ± 0.04 m
Spin3/2
Quadrupole Moment
0.84 ± 0.17
Discovery Year1972
Parity-

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

78Rb

Mass Number78
Neutron Number41
Relative Atomic Mass
G-Factor
0
Abundance
Radioactivity☢️ Radioactive
Half Life
17.66 ± 0.03 m
Spin0
Quadrupole Moment
0
Discovery Year1968
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

79Rb

Mass Number79
Neutron Number42
Relative Atomic Mass
G-Factor
1.34292 ± 0.00048
Abundance
Radioactivity☢️ Radioactive
Half Life
22.9 ± 0.5 m
Spin5/2
Quadrupole Moment
-0.12 ± 0.04
Discovery Year1957
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

80Rb

Mass Number80
Neutron Number43
Relative Atomic Mass
G-Factor
-0.0833 ± 0.0007
Abundance
Radioactivity☢️ Radioactive
Half Life
33.4 ± 0.7 s
Spin1
Quadrupole Moment
0.42 ± 0.08
Discovery Year1961
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

81Rb

Mass Number81
Neutron Number44
Relative Atomic Mass
G-Factor
1.3727333333333 ± 0.00093333333333333
Abundance
Radioactivity☢️ Radioactive
Half Life
4.572 ± 0.004 h
Spin3/2
Quadrupole Moment
0.48 ± 0.1
Discovery Year1949
Parity-

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

82Rb

Mass Number82
Neutron Number45
Relative Atomic Mass
G-Factor
0.554403 ± 0.000016
Abundance
Radioactivity☢️ Radioactive
Half Life
1.2575 ± 0.0002 m
Spin1
Quadrupole Moment
0.23 ± 0.1
Discovery Year1949
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

83Rb

Mass Number83
Neutron Number46
Relative Atomic Mass
G-Factor
0.56984 ± 0.00032
Abundance
Radioactivity☢️ Radioactive
Half Life
86.2 ± 0.1 d
Spin5/2
Quadrupole Moment
0.24 ± 0.05
Discovery Year1950
Parity-

Decay ModeIntensity
ϵ (electron capture)100%

84Rb

Mass Number84
Neutron Number47
Relative Atomic Mass
G-Factor
-0.6625 ± 0.001
Abundance
Radioactivity☢️ Radioactive
Half Life
32.82 ± 0.07 d
Spin2
Quadrupole Moment
-0.02 ± 0.04
Discovery Year1947
Parity-

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)96.1%
β (β decay)3.9%

85Rb

Mass Number85
Neutron Number48
Relative Atomic Mass
G-Factor
0.541224 ± 0.000016
Abundance
72.17 ± 0.02
RadioactivityStable
Half LifeNot Radioactive ☢️
Spin5/2
Quadrupole Moment
0.276 ± 0.001
Discovery Year1921
Parity-

86Rb

Mass Number86
Neutron Number49
Relative Atomic Mass
G-Factor
-0.8487 ± 0.0008
Abundance
Radioactivity☢️ Radioactive
Half Life
18.645 ± 0.008 d
Spin2
Quadrupole Moment
0.23 ± 0.06
Discovery Year1941
Parity-

Decay ModeIntensity
β (β decay)100%
ϵ (electron capture)0.0052%

87Rb

Mass Number87
Neutron Number50
Relative Atomic Mass
G-Factor
1.8341933333333 ± 0.000053333333333333
Abundance
27.83 ± 0.02
Radioactivity☢️ Radioactive
Half Life
49.7 ± 0.3 Gy
Spin3/2
Quadrupole Moment
0.1335 ± 0.0005
Discovery Year1921
Parity-

Decay ModeIntensity
β (β decay)100%

88Rb

Mass Number88
Neutron Number51
Relative Atomic Mass
G-Factor
0.253755 ± 0.00001
Abundance
Radioactivity☢️ Radioactive
Half Life
17.78 ± 0.03 m
Spin2
Quadrupole Moment
-0.01 ± 0.11
Discovery Year1939
Parity-

Decay ModeIntensity
β (β decay)100%

89Rb

Mass Number89
Neutron Number52
Relative Atomic Mass
G-Factor
1.5887333333333 ± 0.00046666666666667
Abundance
Radioactivity☢️ Radioactive
Half Life
15.32 ± 0.1 m
Spin3/2
Quadrupole Moment
0.17 ± 0.03
Discovery Year1940
Parity-

Decay ModeIntensity
β (β decay)100%

90Rb

Mass Number90
Neutron Number53
Relative Atomic Mass
G-Factor
0
Abundance
Radioactivity☢️ Radioactive
Half Life
158 ± 5 s
Spin0
Quadrupole Moment
0
Discovery Year1951
Parity-

Decay ModeIntensity
β (β decay)100%

91Rb

Mass Number91
Neutron Number54
Relative Atomic Mass
G-Factor
1.4540666666667 ± 0.001
Abundance
Radioactivity☢️ Radioactive
Half Life
58.2 ± 0.3 s
Spin3/2
Quadrupole Moment
0.19 ± 0.05
Discovery Year1951
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)

92Rb

Mass Number92
Neutron Number55
Relative Atomic Mass
G-Factor
0
Abundance
Radioactivity☢️ Radioactive
Half Life
4.48 ± 0.03 s
Spin0
Quadrupole Moment
0
Discovery Year1960
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)0.0107%

93Rb

Mass Number93
Neutron Number56
Relative Atomic Mass
G-Factor
0.56368 ± 0.00064
Abundance
Radioactivity☢️ Radioactive
Half Life
5.84 ± 0.02 s
Spin5/2
Quadrupole Moment
0.21 ± 0.06
Discovery Year1960
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)1.39%

94Rb

Mass Number94
Neutron Number57
Relative Atomic Mass
G-Factor
0.49936666666667 ± 0.0006
Abundance
Radioactivity☢️ Radioactive
Half Life
2.702 ± 0.005 s
Spin3
Quadrupole Moment
0.2 ± 0.07
Discovery Year1961
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)10.3%

95Rb

Mass Number95
Neutron Number58
Relative Atomic Mass
G-Factor
0.5332 ± 0.0012
Abundance
Radioactivity☢️ Radioactive
Half Life
377.7 ± 0.8 ms
Spin5/2
Quadrupole Moment
0.26 ± 0.09
Discovery Year1967
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)8.7%

96Rb

Mass Number96
Neutron Number59
Relative Atomic Mass
G-Factor
0.73275 ± 0.00085
Abundance
Radioactivity☢️ Radioactive
Half Life
201.5 ± 0.9 ms
Spin2
Quadrupole Moment
0.3 ± 0.09
Discovery Year1967
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)13.7%
2n (2-neutron emission)

97Rb

Mass Number97
Neutron Number60
Relative Atomic Mass
G-Factor
1.2266666666667 ± 0.0013333333333333
Abundance
Radioactivity☢️ Radioactive
Half Life
169.1 ± 0.6 ms
Spin3/2
Quadrupole Moment
0.7
Discovery Year1969
Parity+

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)25.5%
2n (2-neutron emission)

98Rb

Mass Number98
Neutron Number61
Relative Atomic Mass
G-Factor
0
Abundance
Radioactivity☢️ Radioactive
Half Life
115 ± 6 ms
Spin0
Quadrupole Moment
0
Discovery Year1971
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)14.3%
2n (2-neutron emission)0.054%

99Rb

Mass Number99
Neutron Number62
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
54 ± 4 ms
Spin3/2
Quadrupole Moment
Discovery Year1971
Parity+

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)17.3%
2n (2-neutron emission)

100Rb

Mass Number100
Neutron Number63
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
51.3 ± 1.6 ms
Spin4
Quadrupole Moment
Discovery Year1978
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)5.6%
2n (2-neutron emission)0.15%

101Rb

Mass Number101
Neutron Number64
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
31.8 ± 3.3 ms
Spin3/2
Quadrupole Moment
Discovery Year1992
Parity+

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)28%
2n (2-neutron emission)

102Rb

Mass Number102
Neutron Number65
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
37 ± 4 ms
Spin4
Quadrupole Moment
Discovery Year1995
Parity+

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)65%
2n (2-neutron emission)

103Rb

Mass Number103
Neutron Number66
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
26 ± 11 ms
Spin3/2
Quadrupole Moment
Discovery Year2010
Parity+

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)
2n (2-neutron emission)

104Rb

Mass Number104
Neutron Number67
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin
Quadrupole Moment
Discovery Year2018
Parity

Decay ModeIntensity
β (β decay)
β n (β-delayed neutron emission)
2n (2-neutron emission)
RbMetal.JPG

History

German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed method of flame spectroscopy. The separation of the metal was tried by Bunsen, but he never got samples with more than 18% of Rubidium. The separation of the metal was only accomplished by George de Hevesy, through the hydrolysis of melted rubidium hydroxide. From the Latin word rubidus, deepest red

DiscoverersR. Bunsen, G. Kirchoff
Discovery LocationGermany
Discovery Year1861
Etymology (Name Origin)Latin: rubidus (deep red); the color its salts impart to flames.
Pronunciationroo-BID-i-em (English)
Rubidium is not known to be toxic
Rubidium burns with a reddish-violet flame color

Uses

Rubidium is used as a getter in vacuum tubes and as a photocell component. Rubidium compounds are sometimes used in fireworks to give them a purple color. Rubidium salts are used in glasses and ceramics. Rubidium-87 is slightly radioactive and has been used extensively in dating rocks. Used as a catalyst, photocells, and vacuum and cathode-ray tubes.

Sources

Occurs abundantly, but so widespread that production is limited. Usually obtained from lithium production.

Abundance
Abundance in Earth's crust
Natural Abundance (Oceans)
Natural Abundance (Human Body)
0.00046 %
Natural Abundance (Meteor)
0.00032 %
Natural Abundance (Sun)
0.000003 %
Abundance in Universe
0.000001 %

Nuclear Screening Constants

1s0.7922
2p3.9612
2s9.8432
3d15.3208
3p15.6967
3s15.1573
4p26.1192
4s24.612
5s32.0155

Also Known As

  • Rb
  • element 37
  • 37Rb

Translations

  • Norwegian Bokmålrubidium
  • Frenchrubidium
  • Italianrubidio
  • Polishrubid
  • GermanRubidium
  • Dutchrubidium
  • Spanishrubidio
  • Danishrubidium
  • Hungarianrubídium
  • Afrikaansrubidium
  • Amharicሩቢዲየም
  • Aragoneserubidio
  • Arabicروبيديوم
  • Azerbaijanirubidium
  • Belarusianрубідый
  • Bulgarianрубидий
  • Banglaরুবিডিয়াম
  • Bretonrubidiom
  • Bosnianrubidij
  • Catalanrubidi
  • Corsicanrubidiu
  • Czechrubidium
  • Chuvashрубиди
  • Welshrwbidiwm
  • Greekρουβίδιο
  • Esperantorubidio
  • Estonianrubiidium
  • Basquerubidio
  • Persianروبیدیم
  • Finnishrubidium
  • Friulianrubidi
  • Irishrúbaidiam
  • Galicianrubidio
  • Manxrubiddjum
  • Hakka ChineseRubidium
  • Hebrewרובידיום
  • Hindiरुबिडियम
  • Fiji Hindirubidium
  • Croatianrubidij
  • Armenianռուբիդիում
  • Interlinguarubidium
  • Indonesianrubidium
  • Idorubidio
  • Icelandicrúbidín
  • Japaneseルビジウム
  • Lojbanxunsodna
  • JavaneseRubidium
  • Georgianრუბიდიუმი
  • Kazakhрубидий
  • Kannadaರುಬಿಡಿಯಮ್
  • Korean루비듐
  • Kurdishrubîdyûm
  • Komiрубидий
  • Latinrubidium
  • LuxembourgishRubidium
  • Ligurianrubiddio
  • Lithuanianrubidis
  • Latvianrubīdijs
  • Malayalamറൂബിഡിയം
  • Marathiरुबिडियम
  • Western Mariрубидий
  • Malayrubidium
  • Burmeseရူဘီဒီယမ်
  • Norwegian Nynorskrubidium
  • Occitanrubidi
  • Punjabiਰੁਬੀਡੀਅਮ
  • Western Panjabiروبیڈیم
  • Portugueserubídio
  • Quechuarubidyu
  • Romanianrubidiu
  • Russianрубидий
  • Yakutрубидиум
  • Sicilianrubbidiu
  • Serbo-Croatianrubidijum
  • Slovakrubídium
  • Slovenianrubidij
  • Albanianrubidiumi
  • Serbianрубидијум
  • Saterland FrisianRubidium
  • Swedishrubidium
  • Swahilirubidi
  • Tamilருபீடியம்
  • Thaiรูบิเดียม
  • Tagalogrubidyo
  • Turkishrubidyum
  • Uyghurرۇبىدىي
  • Ukrainianрубідій
  • Uzbekrubidiy
  • Vepsrubidii
  • Vietnameserubiđi
  • Walloonrubidiom
  • Warayrubidyo
  • Kalmykрубидиум
  • Yiddishרובידיום
  • Yorubarubidium
  • Chinese
  • Cebuanorubidyo
  • Macedonianрубидиум
  • Central Kurdishڕۆبیدیۆم
  • Gujaratiરુબિડીયમ
  • Piedmonteserubidi
  • Tatarрубидий
  • Odiaରୁବିଡ଼ିଅମ
  • Somalirubiidhiyaam
  • Newariरुबिडियम
  • Cantonese
  • Literary Chinese
  • Belarusian (Taraskievica orthography)рубід
  • Aromanianrubidiu
  • Kyrgyzрубидий
  • Limburgishrubidium
  • Faroeserubidium
  • Teluguరుబీడియం
  • Scottish Gaelicruibidium
  • Nepaliरुबिडियम
  • Sanskritरुबिडियम
  • Malteserubidju
  • Lombardrubidio
  • Asturianrubidiu
  • Scotsrubidium
  • Portuguese (Brazil)rubídio
  • Paliरुबिडियम
  • Gan Chinese
  • Mongolianрубиди
  • Bhojpuriरुबिडियम
  • cdorubidium
  • Min Nan Chineserubidium
  • Sundaneserubidium
  • Tibetanརུ་བི་ཌིམ།
  • Tajikрубидӣй
  • Lingua Franca Novarubidio
  • Wu Chinese
  • kbprʊpɩdɩyɔm
  • olorubidii
  • Northern Frisianrubiidium
  • Chinese (Traditional)
  • Chinese (Taiwan)
  • Chinese (Simplified)
  • Sardinianrubìdiu
  • English (United Kingdom)rubidium
  • Bashkirрубидий
  • Moroccan Arabicروبيديوم
  • Egyptian Arabicروبيديوم
  • Pashtoروبيډيوم
  • Bikolrubidyo
  • Manipuriꯔꯨꯕꯤꯗꯤꯌꯝ
  • Cornishrubidiom
  • Balineserubidium
  • Skolt Samirubidium
  • Northern Samirubidium
  • Inari Samirubidium
  • Urduروبیڈیئم
  • Korean (North Korea)루비디움
  • ZuluILubimbo