Ruthenium

Ruthenium (Ru)

Hard white metallic transition element. Found with platinum, used as a catalyst in some platinum alloys. Dissolves in fused alkalis, and is not attacked by acids. Reacts with halogens and oxygen at high temperatures. Isolated in 1844 by K.K. Klaus.
Atomic Number44
Atomic Weight101.07
Mass Number102
Group8
Period5
Blockd
Protons44 p+
Neutrons58 n0
Electrons44 e-
Ruthenium a half bar.jpg Animated Bohr Model of Ru (Ruthenium) Enhanced Bohr Model of Ru (Ruthenium) Bohr Model: Ru (Ruthenium) Orbital Diagram of Ru (Ruthenium)

Properties

Atomic Radius
130 pm
Molar Volume
Covalent Radius
125 pm
Metallic Radius
125 pm
Ionic Radius
68 pm
Crystal Radius
82 pm
Van der Waals Radius
213 pm
Density
12.1 g/cm³
Energy
Proton Affinity
774 kJ/mol
Electron Affinity
Ionization Energy
Heat of Vaporization
Heat of Fusion
25.5 kJ/mol
Heat of Formation
650.6 kJ/mol
Electrons
Electron Shells2, 8, 18, 15, 1
Valence Electrons6
Electron Configuration[Kr] 4d7 5s1
Oxidation States-4, -2, 0, 1, 2, 3, 4, 5, 6, 7, 8
Electronegativity
2.2
Electrophilicity
1.4011669093178039 eV/particle
Phases
PhaseSolid
Gas Phase
Boiling Point
4,420.15 K
Melting Point
2,606.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Color
Silver
Appearancesilvery white metallic
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
0.0000064 1/K
Molar Heat Capacity
24.06 J/(mol K)
Specific Heat Capacity
0.238 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
14 MS/m
Electrical Resistivity
0.00000007000000000002 m Ω
Superconducting Point
0.49 K
Magnetism
Typeparamagnetic
Magnetic Susceptibility (Mass)
0.00000000542 m³/Kg
Magnetic Susceptibility (Molar)
0.000000000548 m³/mol
Magnetic Susceptibility (Volume)
0.000067
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal StructureSimple Hexagonal (HEX)
Lattice Constant
2.7 Å
Lattice Anglesπ/2, π/2, 2 π/3
Mechanical Properties
Hardness
6.5 MPa
Bulk Modulus
220 GPa
Shear Modulus
173 GPa
Young Modulus
447 GPa
Poisson Ratio
0.3
Speed of Sound
5,970 m/s
Classification
CategoryTransition metals, Transition metals
CAS GroupVIIIA
IUPAC GroupVIII
Glawe Number61
Mendeleev Number60
Pettifor Number63
Geochemical Classnoble metal
Goldschmidt Classsiderophile
Other
Gas Basicity
751.4 kJ/mol
Dipole Polarizability
72 ± 10 a₀
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
2.6
Neutron Mass Absorption
0.0009
Quantum Numbers5F5
Space Group194 (P63/mmc)

Isotopes of Ruthenium

Stable Isotopes7
Unstable Isotopes34
Radioactive Isotopes34

85Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
84.967117 ± 0.000537 Da
Mass Number85
G-Factor
Half Life
Spin3/2
Quadrupole Moment
Discovery Year2013
Parity-

85Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)%
β+ p (β+-delayed proton emission)%
p (proton emission)%

86Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
85.957305 ± 0.000429 Da
Mass Number86
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year2013
Parity+

86Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)%
β+ p (β+-delayed proton emission)%

87Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
86.950907 ± 0.000429 Da
Mass Number87
G-Factor
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year1995
Parity-

87Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)%
β+ p (β+-delayed proton emission)%

88Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
87.941664 ± 0.000322 Da
Mass Number88
G-Factor
0
Half Life
1.5 ± 0.3 s
Spin0
Quadrupole Moment
0
Discovery Year1994
Parity+

88Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)3.6%

89Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
88.937337849 ± 0.000026 Da
Mass Number89
G-Factor
Half Life
1.32 ± 0.03 s
Spin9/2
Quadrupole Moment
Discovery Year1992
Parity+

89Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)3.1%

90Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
89.930344378 ± 0.000004004 Da
Mass Number90
G-Factor
0
Half Life
11.7 ± 0.9 s
Spin0
Quadrupole Moment
0
Discovery Year1991
Parity+

90Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

91Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
90.92674153 ± 0.000002384 Da
Mass Number91
G-Factor
Half Life
8 ± 0.4 s
Spin9/2
Quadrupole Moment
Discovery Year1983
Parity+

91Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)%

92Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
91.920234373 ± 0.000002917 Da
Mass Number92
G-Factor
0
Half Life
3.65 ± 0.05 m
Spin0
Quadrupole Moment
0
Discovery Year1971
Parity+

92Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

93Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
92.917104442 ± 0.000002216 Da
Mass Number93
G-Factor
Half Life
59.7 ± 0.6 s
Spin9/2
Quadrupole Moment
Discovery Year1972
Parity

93Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

94Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
93.91134286 ± 0.000003374 Da
Mass Number94
G-Factor
0
Half Life
51.8 ± 0.6 m
Spin0
Quadrupole Moment
0
Discovery Year1952
Parity+

94Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

95Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
94.910404415 ± 0.0000102 Da
Mass Number95
G-Factor
0.3444 ± 0.0028
Half Life
1.607 ± 0.004 h
Spin5/2
Quadrupole Moment
Discovery Year1948
Parity+

95Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

96Ru

Abundance
5.54 ± 0.14
Relative Atomic Mass
95.90758891 ± 0.000000182 Da
Mass Number96
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1931
Parity+

96Ru Decay Modes
Decay ModeIntensity
+ (double β+ decay)%

97Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
96.907545776 ± 0.000002965 Da
Mass Number97
G-Factor
0.3148 ± 0.0032
Half Life
2.837 ± 0.0014 d
Spin5/2
Quadrupole Moment
Discovery Year1946
Parity+

97Ru Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

98Ru

Abundance
1.87 ± 0.03
Relative Atomic Mass
97.905286709 ± 0.000006937 Da
Mass Number98
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1944
Parity+

99Ru

Abundance
12.76 ± 0.14
Relative Atomic Mass
98.905930284 ± 0.000000368 Da
Mass Number99
G-Factor
-0.2564 ± 0.002
Half Life
Spin5/2
Quadrupole Moment
0.079 ± 0.004
Discovery Year1931
Parity+

100Ru

Abundance
12.6 ± 0.07
Relative Atomic Mass
99.90421046 ± 0.000000367 Da
Mass Number100
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1931
Parity+

101Ru

Abundance
17.06 ± 0.02
Relative Atomic Mass
100.905573086 ± 0.000000443 Da
Mass Number101
G-Factor
-0.2872 ± 0.0024
Half Life
Spin5/2
Quadrupole Moment
0.46 ± 0.02
Discovery Year1931
Parity+

102Ru

Abundance
31.55 ± 0.14
Relative Atomic Mass
101.904340312 ± 0.000000446 Da
Mass Number102
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1931
Parity+

103Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
102.906314846 ± 0.000000473 Da
Mass Number103
G-Factor
0.13733333333333 ± 0.002
Half Life
39.245 ± 0.008 d
Spin3/2
Quadrupole Moment
0.62 ± 0.02
Discovery Year1945
Parity+

103Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

104Ru

Abundance
18.62 ± 0.27
Relative Atomic Mass
103.905425312 ± 0.000002682 Da
Mass Number104
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1931
Parity+

104Ru Decay Modes
Decay ModeIntensity
(double β decay)%

105Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
104.907745478 ± 0.000002683 Da
Mass Number105
G-Factor
0.2 ± 0.13333333333333
Half Life
4.439 ± 0.011 h
Spin3/2
Quadrupole Moment
Discovery Year1945
Parity+

105Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

106Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
105.907328181 ± 0.000005787 Da
Mass Number106
G-Factor
0
Half Life
371.8 ± 1.8 d
Spin0
Quadrupole Moment
0
Discovery Year1948
Parity+

106Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

107Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
106.909969837 ± 0.00000931 Da
Mass Number107
G-Factor
Half Life
3.75 ± 0.05 m
Spin5/2
Quadrupole Moment
Discovery Year1951
Parity

107Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

108Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
107.910185793 ± 0.000009318 Da
Mass Number108
G-Factor
0
Half Life
4.55 ± 0.05 m
Spin0
Quadrupole Moment
0
Discovery Year1955
Parity+

108Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

109Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
108.913323707 ± 0.000009612 Da
Mass Number109
G-Factor
Half Life
34.4 ± 0.2 s
Spin5/2
Quadrupole Moment
Discovery Year1967
Parity+

109Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

110Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
109.914038501 ± 0.00000958 Da
Mass Number110
G-Factor
0
Half Life
12.04 ± 0.17 s
Spin0
Quadrupole Moment
0
Discovery Year1970
Parity+

110Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

111Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
110.917567566 ± 0.000010394 Da
Mass Number111
G-Factor
Half Life
2.12 ± 0.07 s
Spin5/2
Quadrupole Moment
Discovery Year1971
Parity+

111Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

112Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
111.918806922 ± 0.000010305 Da
Mass Number112
G-Factor
0
Half Life
1.75 ± 0.07 s
Spin0
Quadrupole Moment
0
Discovery Year1970
Parity+

112Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

113Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
112.922846729 ± 0.000041097 Da
Mass Number113
G-Factor
Half Life
800 ± 50 ms
Spin1/2
Quadrupole Moment
0
Discovery Year1988
Parity+

113Ru Decay Modes
Decay ModeIntensity
β (β decay)100%

114Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
113.92461443 ± 0.000003817 Da
Mass Number114
G-Factor
0
Half Life
540 ± 30 ms
Spin0
Quadrupole Moment
0
Discovery Year1991
Parity+

114Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

115Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
114.929033049 ± 0.000027016 Da
Mass Number115
G-Factor
Half Life
318 ± 19 ms
Spin1/2
Quadrupole Moment
0
Discovery Year1992
Parity+

115Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

116Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
115.931219191 ± 0.000004 Da
Mass Number116
G-Factor
0
Half Life
204 ± 6 ms
Spin0
Quadrupole Moment
0
Discovery Year1994
Parity+

116Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

117Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
116.936135 ± 0.000465 Da
Mass Number117
G-Factor
Half Life
151 ± 3 ms
Spin3/2
Quadrupole Moment
Discovery Year1994
Parity+

117Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

118Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
117.938808 ± 0.000215 Da
Mass Number118
G-Factor
0
Half Life
99 ± 3 ms
Spin0
Quadrupole Moment
0
Discovery Year1994
Parity+

118Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

119Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
118.94409 ± 0.000322 Da
Mass Number119
G-Factor
Half Life
69.5 ± 2 ms
Spin3/2
Quadrupole Moment
Discovery Year1997
Parity+

119Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

120Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
119.946623 ± 0.000429 Da
Mass Number120
G-Factor
0
Half Life
45 ± 2 ms
Spin0
Quadrupole Moment
0
Discovery Year2010
Parity+

120Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

121Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
120.952098 ± 0.000429 Da
Mass Number121
G-Factor
Half Life
29 ± 2 ms
Spin3/2
Quadrupole Moment
Discovery Year2010
Parity+

121Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

122Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
121.955147 ± 0.000537 Da
Mass Number122
G-Factor
0
Half Life
25 ± 1 ms
Spin0
Quadrupole Moment
0
Discovery Year2010
Parity+

122Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

123Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
122.960762 ± 0.000537 Da
Mass Number123
G-Factor
Half Life
19 ± 2 ms
Spin3/2
Quadrupole Moment
Discovery Year2010
Parity+

123Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

124Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
123.96394 ± 0.000644 Da
Mass Number124
G-Factor
0
Half Life
15 ± 3 ms
Spin0
Quadrupole Moment
0
Discovery Year2010
Parity+

124Ru Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

125Ru

AbundanceRadioactive ☢️
Relative Atomic Mass
124.969544 ± 0.000322 Da
Mass Number125
G-Factor
Half Life
Spin3/2
Quadrupole Moment
Discovery Year2018
Parity+

125Ru Decay Modes
Decay ModeIntensity
β (β decay)%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

History

Jędrzej Śniadecki isolated the element in 1807, but his work was not ratified. Jöns Berzelius and Gottfried Osann nearly discovered ruthenium in 1827. In 1844, Karl Ernst Claus confirmed that there was a new element and isolated ruthenium from the platinum residues of the rouble production while he was working in Kazan University, Kazan. From the Latin word Ruthenia, Russia

DiscoverersKarl Klaus
Discovery LocationRussia
Discovery Year1844
Etymology (Name Origin)Latin: Ruthenia (Russia).
Pronunciationroo-THE-ni-em (English)
Ruthenium is a suspected carcinogen and its compounds strongly stain the skin
Ruthenium is unaffected by air, water and acids

Uses

Ruthenium is used in platinum and palladium alloys to make wear-resistant electrical contacts. Ruthenium dioxide and lead and bismuth ruthenates are used in thick-film chip resistors. Fountain pen nibs are frequently tipped with alloys containing ruthenium. Ruthenium is a versatile catalyst. Used to harden platinum and palladium. Aircraft magnetos use platinum alloy with 10% ruthenium.

Sources

Found in pentlandite and pyroxinite.

Abundance
Abundance in Earth's crust
0.001 mg/kg
Abundance in Oceans
0.0000007 mg/L
Abundance in Human Body
Abundance in Meteor
0.000081 %
Abundance in Sun
0.0000005 %
Abundance in Universe
0.0000004 %

Nuclear Screening Constants

1s0.9077
2p4.0492
2s11.6202
3d14.6411
3p16.7789
3s16.3988
4d31.1872
4p27.5652
4s26.344
5s37.5155