Praseodymium (Pr)

Praseodymium is the 59th element in the periodic table and has a symbol of Pr and atomic number of 59. It has an atomic weight of 140.90766 and a mass number of 141. Praseodymium has fifty-nine protons and eighty-two neutrons in its nucleus, and fifty-nine electrons in six shells. It is located in group zero, period six and block f of the periodic table. Soft silvery metallic element, belongs to the lanthanoids. Only natural isotope is Pr-141 which is not radioactive. Fourteen radioactive isotopes have been artificially produced. Used in rare-earth alloys. Discovered in 1885 by C.A. von Welsbach.

Atomic Number	59
Atomic Weight	140.90766
Mass Number	141

Group
Period	6
Block	f

Protons	59 p⁺
Neutrons	82 n⁰
Electrons	59 e^-

Animated Bohr Model of Pr (Praseodymium)

Properties

Physical Properties
Atomic Radius	185 pm 286 pm
Molar Volume	20.8 cm³/mol
Covalent Radius	176 pm 138 pm 128 pm 203 pm
Metallic Radius
Ionic Radius	99 pm 112.6 pm 117.9 pm 85 pm 96 pm
Crystal Radius	113 pm 126.6 pm 131.9 pm 99 pm 110 pm
Van der Waals Radius	240 pm 273 pm 360.6 pm
Density	6.773 g/cm³ 6,500 kg/m³
Energy
Proton Affinity
Electron Affinity	0.962 eV/particle
Ionization Energy	5.473 eV/particle 10.55 eV/particle 21.6237 eV/particle 38.98 eV/particle 57.5 eV/particle 82 eV/particle 97 eV/particle 112 eV/particle 131 eV/particle 148 eV/particle 162 eV/particle 196 eV/particle 217.02 eV/particle 350 eV/particle 378 eV/particle 412 eV/particle 445 eV/particle 478 eV/particle 516 eV/particle 554 eV/particle 590 eV/particle 627 eV/particle 663 eV/particle 803 eV/particle 840 eV/particle 880 eV/particle 920 eV/particle 985 eV/particle 1,028 eV/particle 1,124 eV/particle 1,169.94 eV/particle 2,019 eV/particle 2,108 eV/particle 2,202 eV/particle 2,304 eV/particle 2,400 eV/particle 2,501 eV/particle 2,628 eV/particle 2,729 eV/particle 2,838 eV/particle 2,941 eV/particle 3,227 eV/particle 3,319 eV/particle 3,419 eV/particle 3,512 eV/particle 3,729 eV/particle 3,832 eV/particle 4,030 eV/particle 4,130 eV/particle 9,378 eV/particle 9,632 eV/particle 9,913 eV/particle 10,175 eV/particle 10,959 eV/particle 11,262 eV/particle 11,641 eV/particle 11,895.89 eV/particle 48,571.71 eV/particle 49,722.2 eV/particle

Heat of Vaporization	331 kJ/mol
Heat of Fusion	11.3 kJ/mol
Heat of Formation	356.9 kJ/mol
Electrons
Electron Shells	2, 8, 18, 21, 8, 2

Valence Electrons	2

Electron Configuration	[Xe] 4f³ 6s²

Oxidation States	0, 1, 2, 3, 4, 5
Electronegativity	0.17208 1.13
Electrophilicity	1.1474513688760803 eV/particle
Phases
Phase	Solid
Gas Phase
Boiling Point	3,793.15 K
Melting Point	1,204.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Praseodymium is a Silver. Pr has a CPK of #ff1493, Jmol of #d9ffc7, and MOLCAS GV of #d9ffc7. The Appearance of Element 59 is grayish white.
Color	Silver #ff1493 #d9ffc7 #d9ffc7
Appearance	grayish white
Refractive Index
Thermodynamic Properties
Thermal Conductivity	12.5 W/(m K)
Thermal Expansion	0.0000067 1/K
Molar Heat Capacity	27.2 J/(mol K)
Specific Heat Capacity	0.193 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
Type	Conductor
Electrical Conductivity	1.4 MS/m
Electrical Resistivity	0.0000007 m Ω
Superconducting Point
Magnetism
Type	paramagnetic
Magnetic Susceptibility (Mass)	0.000000423 m³/Kg
Magnetic Susceptibility (Molar)	0.000000059604 m³/mol
Magnetic Susceptibility (Volume)	0.0028087
Magnetic Ordering
Curie Point
Neel Point
Structure
The Crystal Structure of Praseodymium is HEX. The lattice constant of Pr is 3.67 Å. The lattice angles of Element 59 are π/2, π/2, 2 π/3.
Crystal Structure	Simple Hexagonal (HEX)
Lattice Constant	3.67 Å
Lattice Angles	π/2, π/2, 2 π/3
Mechanical Properties
Praseodymium has a Brinell of 481 MPa, and Vickers of 400 MPa. The Bulk Modulus of Pr is 29 GPa. The Shear Modulus of Element 59 is 15 GPa. The Young Modulus of Praseodymium (Pr) is 37 GPa. The Poisson Ratio of Praseodymium is 0.28. The Speed of Sound of Pr is 2280 m/s.
Hardness	481 MPa 400 MPa
Bulk Modulus	29 GPa
Shear Modulus	15 GPa
Young Modulus	37 GPa
Poisson Ratio	0.28
Speed of Sound	2,280 m/s
Classification
The Glawe Number of Praseodymium is 30. The Mendeleev Number of Pr is 17. The Pettifor Number of Element 59 is 31. The Geochemical Class of Praseodymium (Pr) is rare earth & related. The Goldschmidt Class of Praseodymium is litophile.
Category	Lanthanides, Lanthanides
CAS Group
IUPAC Group
Glawe Number	30
Mendeleev Number	17
Pettifor Number	31
Geochemical Class	rare earth & related
Goldschmidt Class	litophile
Other
The Dipole Polarizability of Praseodymium is 216 plus or minus 20 a₀. Pr has a C6 Dispersion Coefficient (GB) of 3760 a₀. The Allotropes of Element 59 is . The Neutron Cross Section of Praseodymium (Pr) is 11.4. The Neutron Mass Absorption of Praseodymium is 0.0029. The Quantum Numbers of Pr is 4I9/2. The Space Group of Element 59 is 194 (P63/mmc).
Gas Basicity
Dipole Polarizability	216 ± 20 a₀
C6 Dispersion Coefficient	3,760 a₀
Allotropes
Neutron Cross Section	11.4
Neutron Mass Absorption	0.0029
Quantum Numbers	4I9/2
Space Group	194 (P63/mmc)

Isotopes of Praseodymium

Stable Isotopes	1
Unstable Isotopes	40
Radioactive Isotopes	40

¹²¹Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	120.955393 ± 0.000537 Da
Mass Number	121
G-Factor
Half Life	12 ± 5 ms
Spin	3/2
Quadrupole Moment
Discovery Year	2005
Parity

¹²¹Pr Decay Modes

Decay Mode	Intensity
p (proton emission)	100%

¹²²Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	121.951927 ± 0.000537 Da
Mass Number	122
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

¹²²Pr Decay Modes

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

¹²³Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	122.946076 ± 0.000429 Da
Mass Number	123
G-Factor
Half Life
Spin	3/2
Quadrupole Moment
Discovery Year
Parity	+

¹²³Pr Decay Modes

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

¹²⁴Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	123.94294 ± 0.00043 Da
Mass Number	124
G-Factor
Half Life	1.2 ± 0.2 s
Spin
Quadrupole Moment
Discovery Year	1986
Parity

¹²⁴Pr Decay Modes

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

¹²⁵Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	124.937659 ± 0.000322 Da
Mass Number	125
G-Factor
Half Life	3.3 ± 0.7 s
Spin	3/2
Quadrupole Moment
Discovery Year	2002
Parity	+

¹²⁵Pr Decay Modes

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

¹²⁶Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	125.93524 ± 0.00021 Da
Mass Number	126
G-Factor
Half Life	3.12 ± 0.18 s
Spin	4
Quadrupole Moment
Discovery Year	1983
Parity

¹²⁶Pr Decay Modes

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

¹²⁷Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	126.93071 ± 0.00021 Da
Mass Number	127
G-Factor
Half Life	4.2 ± 0.3 s
Spin	3/2
Quadrupole Moment
Discovery Year	1995
Parity	+

¹²⁷Pr Decay Modes

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

¹²⁸Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	127.928791 ± 0.000032 Da
Mass Number	128
G-Factor
Half Life	2.85 ± 0.09 s
Spin	3
Quadrupole Moment
Discovery Year	1985
Parity	+

¹²⁸Pr Decay Modes

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

¹²⁹Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	128.925095 ± 0.000032 Da
Mass Number	129
G-Factor
Half Life	30 ± 4 s
Spin	3/2
Quadrupole Moment
Discovery Year	1977
Parity	+

¹²⁹Pr Decay Modes

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

¹³⁰Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	129.92359 ± 0.000069 Da
Mass Number	130
G-Factor
Half Life	40 ± 0.4 s
Spin	6
Quadrupole Moment
Discovery Year	1977
Parity

¹³⁰Pr Decay Modes

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

¹³¹Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	130.92023496 ± 0.000050451 Da
Mass Number	131
G-Factor
Half Life	1.5 ± 0.03 m
Spin	3/2
Quadrupole Moment
Discovery Year	1977
Parity	+

¹³¹Pr Decay Modes

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

¹³²Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	131.91924 ± 0.000031 Da
Mass Number	132
G-Factor
Half Life	1.49 ± 0.11 m
Spin	2
Quadrupole Moment
Discovery Year	1974
Parity	+

¹³²Pr Decay Modes

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

¹³³Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	132.916330558 ± 0.000013416 Da
Mass Number	133
G-Factor
Half Life	6.5 ± 0.3 m
Spin	5/2
Quadrupole Moment
Discovery Year	1970
Parity	+

¹³³Pr Decay Modes

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

¹³⁴Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	133.915696729 ± 0.00002181 Da
Mass Number	134
G-Factor
Half Life	17 ± 2 m
Spin	2
Quadrupole Moment
Discovery Year	1967
Parity	-

¹³⁴Pr Decay Modes

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

¹³⁵Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	134.913111772 ± 0.000012686 Da
Mass Number	135
G-Factor
Half Life	24 ± 1 m
Spin	3/2
Quadrupole Moment
Discovery Year	1954
Parity	+

¹³⁵Pr Decay Modes

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

¹³⁶Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	135.91267747 ± 0.000012296 Da
Mass Number	136
G-Factor
Half Life	13.1 ± 0.1 m
Spin	2
Quadrupole Moment
Discovery Year	1968
Parity	+

¹³⁶Pr Decay Modes

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

¹³⁷Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	136.910679183 ± 0.000008733 Da
Mass Number	137
G-Factor
Half Life	1.28 ± 0.03 h
Spin	5/2
Quadrupole Moment
Discovery Year	1958
Parity	+

¹³⁷Pr Decay Modes

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

¹³⁸Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	137.910757495 ± 0.000010748 Da
Mass Number	138
G-Factor
Half Life	1.45 ± 0.05 m
Spin	1
Quadrupole Moment
Discovery Year	1951
Parity	+

¹³⁸Pr Decay Modes

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

¹³⁹Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	138.9089327 ± 0.000003917 Da
Mass Number	139
G-Factor
Half Life	4.41 ± 0.04 h
Spin	5/2
Quadrupole Moment
Discovery Year	1951
Parity	+

¹³⁹Pr Decay Modes

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

¹⁴⁰Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	139.9090856 ± 0.000006593 Da
Mass Number	140
G-Factor
Half Life	3.39 ± 0.01 m
Spin	1
Quadrupole Moment
Discovery Year	1938
Parity	+

¹⁴⁰Pr Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
e⁺ (positron emission)	48.7%
ϵ (electron capture)	51.3%

¹⁴¹Pr

Abundance	100
Relative Atomic Mass	140.907659604 ± 0.000001607 Da
Mass Number	141
G-Factor	1.7064 ± 0.0012
Half Life
Spin	5/2
Quadrupole Moment	-0.077 ± 0.006
Discovery Year	1924
Parity	+

¹⁴²Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	141.91005164 ± 0.000001607 Da
Mass Number	142
G-Factor	0.117 ± 0.0005
Half Life	19.12 ± 0.04 h
Spin	2
Quadrupole Moment	0.039 ± 0.017
Discovery Year	1935
Parity	-

¹⁴²Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
ϵ (electron capture)	0.0164%

¹⁴³Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	142.910822624 ± 0.000001949 Da
Mass Number	143
G-Factor	0.77 ± 0.0014285714285714
Half Life	13.57 ± 0.02 d
Spin	7/2
Quadrupole Moment	0.77 ± 0.16
Discovery Year	1948
Parity	+

¹⁴³Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁴Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	143.913310682 ± 0.000002907 Da
Mass Number	144
G-Factor	0
Half Life	17.28 ± 0.05 m
Spin	0
Quadrupole Moment	0
Discovery Year	1951
Parity	-

¹⁴⁴Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁵Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	144.914517987 ± 0.000007674 Da
Mass Number	145
G-Factor
Half Life	5.984 ± 0.01 h
Spin	7/2
Quadrupole Moment
Discovery Year	1954
Parity	+

¹⁴⁵Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁶Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	145.91768763 ± 0.000036882 Da
Mass Number	146
G-Factor
Half Life	24.09 ± 0.1 m
Spin	2
Quadrupole Moment
Discovery Year	1953
Parity	-

¹⁴⁶Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁷Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	146.919007438 ± 0.00001702 Da
Mass Number	147
G-Factor
Half Life	13.39 ± 0.04 m
Spin	3/2
Quadrupole Moment
Discovery Year	1964
Parity	+

¹⁴⁷Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁸Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	147.922129992 ± 0.000016147 Da
Mass Number	148
G-Factor
Half Life	2.29 ± 0.02 m
Spin	1
Quadrupole Moment
Discovery Year	1964
Parity	-

¹⁴⁸Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁹Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	148.9237361 ± 0.0000106 Da
Mass Number	149
G-Factor
Half Life	2.26 ± 0.07 m
Spin	5/2
Quadrupole Moment
Discovery Year	1964
Parity	+

¹⁴⁹Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁵⁰Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	149.926676391 ± 0.000009677 Da
Mass Number	150
G-Factor
Half Life	6.19 ± 0.16 s
Spin	1
Quadrupole Moment
Discovery Year	1970
Parity	-

¹⁵⁰Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁵¹Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	150.928309066 ± 0.000012506 Da
Mass Number	151
G-Factor
Half Life	18.9 ± 0.07 s
Spin	3/2
Quadrupole Moment
Discovery Year	1990
Parity	-

¹⁵¹Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁵²Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	151.9315529 ± 0.0000199 Da
Mass Number	152
G-Factor
Half Life	3.57 ± 0.11 s
Spin	4
Quadrupole Moment
Discovery Year	1983
Parity	+

¹⁵²Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁵³Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	152.933903511 ± 0.000012755 Da
Mass Number	153
G-Factor
Half Life	4.28 ± 0.11 s
Spin	3/2
Quadrupole Moment
Discovery Year	1987
Parity	-

¹⁵³Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁵⁴Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	153.937885165 ± 0.00010736 Da
Mass Number	154
G-Factor
Half Life	2.3 ± 0.09 s
Spin	3
Quadrupole Moment
Discovery Year	1988
Parity	+

¹⁵⁴Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁵⁵Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	154.940509193 ± 0.000018462 Da
Mass Number	155
G-Factor
Half Life	1.47 ± 0.3 s
Spin	3/2
Quadrupole Moment
Discovery Year	1992
Parity	-

¹⁵⁵Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁵⁶Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	155.9447669 ± 0.0000011 Da
Mass Number	156
G-Factor
Half Life	444 ± 6 ms
Spin	1
Quadrupole Moment
Discovery Year	1992
Parity	+

¹⁵⁶Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁵⁷Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	156.9480031 ± 0.0000034 Da
Mass Number	157
G-Factor
Half Life	307 ± 21 ms
Spin	3/2
Quadrupole Moment
Discovery Year	2017
Parity	-

¹⁵⁷Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁵⁸Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	157.952603 ± 0.000322 Da
Mass Number	158
G-Factor
Half Life	181 ± 14 ms
Spin	5
Quadrupole Moment
Discovery Year	2016
Parity	-

¹⁵⁸Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁵⁹Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	158.956232 ± 0.000429 Da
Mass Number	159
G-Factor
Half Life	134 ± 43 ms
Spin	3/2
Quadrupole Moment
Discovery Year	2017
Parity	-

¹⁵⁹Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁶⁰Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	159.961138 ± 0.000429 Da
Mass Number	160
G-Factor
Half Life	170 ± 140 ms
Spin	1
Quadrupole Moment
Discovery Year	2017
Parity	+

¹⁶⁰Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁶¹Pr

Abundance	Radioactive ☢️
Relative Atomic Mass	160.965121 ± 0.000537 Da
Mass Number	161
G-Factor
Half Life
Spin	3/2
Quadrupole Moment
Discovery Year	2018
Parity	-

¹⁶¹Pr Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	%
β⁻ n (β⁻-delayed neutron emission)	%

History

Praseodymium was first identified in 1885, in Vienna, by the Austrian chemist Carl Auer von Welsbach. It was discovered in didymium, a substance incorrectly said by Carl Gustav Mosander to be a new element in 1841. Pure metallic praseodymium was first produced in 1931. From the Greek word prasios, green, and didymos, twin

Discoverers	C.F. Aver von Welsbach
Discovery Location	Austria
Discovery Year	1885
Etymology (Name Origin)	Greek: prasios and didymos (green twin); from its green salts.
Pronunciation	pra-si-eh-DIM-i-em (English)

Praseodymium is considered to be moderately toxic

Praseodymium is usually stored under a light mineral oil or sealed in glass

Uses

Praseodymium is used as an alloying agent with magnesium to create high-strength metals that are used in aircraft engines. Misch metal, used in making cigarette lighters, contains about 5% praseodymium metal. Praseodymium is used to make specialized yellow glass goggles for glass blowers and welders. Used with neodymium to make lenses for glass maker's goggles since it filters out the yellow light present in glass blowing. Alloyed with magnesium creates a high-strength metal used in aircraft engines. Makes up 5% of Mich metal.

Sources

Obtained from same salts as neodymium.

Abundance
Abundance in Earth's crust	9.2 mg/kg
Abundance in Oceans	0.00000064 mg/L
Abundance in Human Body
Abundance in Meteor	0.0000098 %
Abundance in Sun	0.0000001 %
Abundance in Universe	0.0000002 %

Nuclear Screening Constants

1	s	1.1694
2	p	4.2306
2	s	15.538
3	d	13.8476
3	p	19.1756
3	s	19.499
4	d	32.7028
4	f	37.8992
4	p	29.9432
4	s	28.6668
5	p	43.7165
5	s	41.387
6	s	51.2534

Praseodymium on ChemicalAid

Australian Educational Vocabulary ID	scot/3561
CAS Registry Number	7440-10-0
ChEBI ID	49828
ChemSpider ID	22384
DSSTOX compound identifier	DTXCID2047648
DSSTox substance ID	DTXSID4064684
Den Store Danske ID	praseodym
ECHA Substance Infocard ID	100.028.291
Elhuyar ZTH ID	030065
Encyclopædia Britannica Online ID	science/praseodymium
Encyclopædia Universalis ID	praseodyme
Freebase ID	/m/025sc08
GND ID	4175591-1
Gran Enciclopèdia Catalana ID	0134006
Great Russian Encyclopedia Online ID	3173701
InChI	InChI=1S/Pr
InChIKey	PUDIUYLPXJFUGB-UHFFFAOYSA-N
KBpedia ID	Praseodymium
Library of Congress authority ID	sh85106095
MeSH descriptor ID	D011221
Namuwiki ID	프라세오디뮴
National Library of Israel J9U ID	987007531660105171
OmegaWiki Defined Meaning	342115
OpenAlex ID	C537997061
PubChem CID	23942
Quora topic ID	Praseodymium
RxNorm ID	1311481
Römpp online ID	RD-16-03954
Store norske leksikon ID	praseodym
Treccani ID	praseodimio
UNII	NKN7EZA750
USGS Thesaurus ID	1545
WordNet 3.1 Synset ID	14675391-n

Praseodymium (Pr)

Properties

Isotopes of Praseodymium

121Pr

121Pr Decay Modes

122Pr

122Pr Decay Modes

123Pr

123Pr Decay Modes

124Pr

124Pr Decay Modes

125Pr

125Pr Decay Modes

126Pr

126Pr Decay Modes

127Pr

127Pr Decay Modes

128Pr

128Pr Decay Modes

129Pr

129Pr Decay Modes

130Pr

130Pr Decay Modes

131Pr

131Pr Decay Modes

132Pr

132Pr Decay Modes

133Pr

133Pr Decay Modes

134Pr

134Pr Decay Modes

135Pr

135Pr Decay Modes

136Pr

136Pr Decay Modes

137Pr

137Pr Decay Modes

138Pr

138Pr Decay Modes

139Pr

139Pr Decay Modes

140Pr

140Pr Decay Modes

141Pr

142Pr

142Pr Decay Modes

143Pr

143Pr Decay Modes

144Pr

144Pr Decay Modes

145Pr

145Pr Decay Modes

146Pr

146Pr Decay Modes

147Pr

147Pr Decay Modes

148Pr

148Pr Decay Modes

149Pr

149Pr Decay Modes

150Pr

150Pr Decay Modes

151Pr

151Pr Decay Modes

152Pr

152Pr Decay Modes

153Pr

153Pr Decay Modes

154Pr

154Pr Decay Modes

155Pr

155Pr Decay Modes

156Pr

156Pr Decay Modes

157Pr

157Pr Decay Modes

158Pr

158Pr Decay Modes

159Pr

159Pr Decay Modes