91 – Protactinium, Pa

PERIODIC TABLE

Spectrograph
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Elemental Tile
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Protactinium Torbernite
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Protactinium is a dense, silvery-grey metal which readily reacts with oxygen, water vapour and inorganic acids. The average concentrations in the Earth’s crust is in the order of a few parts per trillion, but may reach up to a few parts per million in some uraninite ore deposits. Due to its scarcity, high radioactivity and high toxicity, there are currently no uses for protactinium outside of scientific research, and for this purpose, protactinium is mostly extracted from spent nuclear fuel.

1913 by Otto Hahn, Lise Meitner, Frederick Soddy and John Cranston, Germany.

DISCOVERY

Greek 'protos' meaning 'first'.

ETYMOLOGY

Protactinium

Element

Pa

Symbol

91 Atomic Number

Actinide

Classification

7440-13-3

CAS Number

Silver

Elemental Colour

-

Refractive Index

-

Poisson Ratio

15.032 cm³

Molar Volume

-

Brinell Hardness

-

Mohs Hardness

-

Vickers Hardness

-

Speed of Sound

-

Bulk Modulus

-

Shear Modulus

-

Young Modulus

Allotropes

1,845.15 K, 1,572.00 °C

1,572.00 °C

Melting Point

4,273.15 K, 4,000.00 °C

4,000.00 °C

Boiling Point

-

Automatic Ignition

-

Flashpoint

-

Critical Temperature

-

Critical Pressure

47.000'000 W/(m K)

Thermal Conductivity

-

Thermal Expansion

99.10 J/(kg K)

Specific Heat

15.000 kJ/mol

Heat Fusion

470.000 kJ/mol

Heat Vaporisation

-

Heat Combustion

-

Curie Point

-

Neel Point

-

Adiabatic Index

Solid

Phase

Conductor

Electrical Type

5.60M S/m

Conductivity

180.00n Ω.m

Resistivity

1.400 K

Superconducting Point

-

Magnetic Type

0.000'000'032'5

Mass Susceptibility

0.000'000'007'509'00

Molar Susceptibility

0.000'499'500'00

Volume Susceptibility

Material Composition

-

Universe

-

Meteorites

-

Sun

0.000'000'000'81 %

Earth Crust

2 x 10 ^-23 %

Oceans

-

Humans

231.035'884'2

Atomic Weight

161 pm

Atomic Radius

169 pm

Covalent Radius Single Bond

138 pm

Covalent Radius Double Bond

129 pm

Covalent Radius Triple Bond

243 pm

Van der Waals Radius

[Rn]7s²5f²6d¹

Electron Configuration

Tetragonal, Primitive

Crystal Structure

15.370'00 g/cm³

Density as Solid

-

Density as Liquid

-

Density as Gas

I4/mmm

Space Group Name

139 Space Group Number

π/2, π/2 & π/2

Lattice Angles

392.5, 392.5 & 323.8 pm

Lattice Constants

32,788 years

Half Life

47,279 years

Lifetime

6d¹ = 6, 2, -2, +1/2

Quantum Numbers

10.500'00 b σ_s

Neutron Cross Section

200.600'00 b σ_a

Neutron Mass Absorption

Stable Isotopes

NONE

Unstable Isotopes

Isotopes Overview

Isotope	Stability	Symbol	Type	Protons		Neutrons		Spin	Parity	Mass		Abundance		Mass Measure	Mass Excess		Binding Energy		Dipole Moment		Quadrupole Moment		Halflife in Years		Halflife in Seconds		A01 Decay Probability		A01 Decay Mode	A01 Decay Energy		A01 Decay Daughter	A01 Decay Link	A02 Decay Mode	A02 Decay Energy		A02 Decay Daughter	A02 Decay Link	A03 Decay Probability		A03 Decay Mode	A03 Decay Energy		A03 Decay Daughter	A03 Decay Link	A04 Decay Probability		A04 Decay Mode	A04 Decay Energy		Y01 Decay Product Yield		Y01 Decay Product Nuclide	Y02 Decay Product Yield		Y02 Decay Product Nuclide	Y03 Decay Product Yield		Y03 Decay Product Nuclide	Y04 Decay Product Yield		Y04 Decay Product Nuclide	Y05 Decay Product Yield		Y05 Decay Product Nuclide	Y06 Decay Product Yield		Y06 Decay Product Nuclide	Y07 Decay Product Yield		Y07 Decay Product Nuclide	Y08 Decay Product Yield		Y08 Decay Product Nuclide	Y09 Decay Product Yield		Y09 Decay Product Nuclide	Y10 Decay Product Yield		Y10 Decay Product Nuclide	Y11 Decay Product Yield		Y11 Decay Product Nuclide	Y12 Decay Product Yield		Y12 Decay Product Nuclide
Isotope_091_pa_212_u	Unstable	²¹²Pa	Boson	91	p	121	n	7	1	212.023'204'138'0	u	~ 0	%	~ 0	52.625'000'000'0	MeV	7.554'000'000'0	MeV	-		-		2.54E-10	year	8.000	milli-seconds ( x⁻³ )	100.000'000	%	α	8,429.400	keV	²⁰⁸Ac	²¹²Pa > [ 100 % , α , 8,429.4 keV ] > ²⁰⁸Ac																		36.949'478	%	²⁰⁰Hg	0.000'641	%	¹⁹²Pt	0.000'000	%	²⁰⁸Pb	0.000'000	%	¹⁶⁰Dy	0.000'000	%	¹⁴⁰Ce	?	%	¹⁷²Yb	?	%	¹⁷⁶Hf	?	%	¹⁵²Sm	?	%	¹⁸⁰Hf	?	%	¹⁵⁶Gd	?	%	¹⁶⁸Er	?	%	¹⁶⁴Dy
Isotope_091_pa_213_u	Unstable	²¹³Pa	Fermion	91	p	122	n	9/2	-1	213.021'109'340'0	u	~ 0	%	~ 0	21.614'516'000'0	MeV	7.633'543'000'0	MeV	-		-		2.22E-10	year	7.000	milli-seconds ( x⁻³ )	100.000'000	%	α	8,393.900	keV	²⁰⁹Ac	²¹³Pa > [ 100 % , α , 8,393.9 keV ] > ²⁰⁹Ac																		70.756'344	%	¹⁹⁷Au	28.833'371	%	²⁰¹Hg	1.400'912	%	²⁰⁵Tl	0.000'000	%	¹⁸⁸Os	?	%	¹⁹⁶Pt	?	%	¹⁸⁰Hf	?	%	¹⁷⁶Hf
Isotope_091_pa_214_u	Unstable	²¹⁴Pa	Boson	91	p	123	n	?	0	214.020'918'417'0	u	~ 0	%	~ 0	19.663'224'000'0	MeV	7.644'760'000'0	MeV	-		-		5.39E-10	year	17.000	milli-seconds ( x⁻³ )	100.000'000	%	α	8,270.900	keV	²¹⁰Ac	²¹⁴Pa > [ 100 % , α , 8,270.9 keV ] > ²¹⁰Ac																		69.577'454	%	²⁰²Hg	22.204'307	%	²⁰⁶Pb	8.908'261	%	¹⁹⁸Hg	0.000'070	%	¹⁹³Ir	0.000'000	%	¹⁸⁹Os
Isotope_091_pa_215_u	Unstable	²¹⁵Pa	Fermion	91	p	124	n	9/2	-1	215.019'185'865'0	u	~ 0	%	~ 0	19.485'380'000'0	MeV	7.647'584'000'0	MeV	-		-		4.44E-10	year	14.000	milli-seconds ( x⁻³ )	100.000'000	%	α	8,241.700	keV	²¹¹Ac	²¹⁵Pa > [ 100 % , α , 8,241.7 keV ] > ²¹¹Ac																		66.993'149	%	²⁰³Tl	29.523'310	%	¹⁹⁹Hg	3.757'640	%	²⁰⁷Pb
Isotope_091_pa_216_u	Unstable	²¹⁶Pa	Boson	91	p	125	n	?	0	216.019'109'564'0	u	~ 0	%	~ 0	17.871'519'000'0	MeV	7.657'061'000'0	MeV	-		-		3.33E-9	year	105.000	milli-seconds ( x⁻³ )	98.000'000	%	α	8,097.000	keV	²¹²Ac	²¹⁶Pa > [ 98 % , α , 8,097.0 keV ] > ²¹²Ac	β+	6,474.000	keV	²¹⁶Th	²¹⁶Pa > [ , β+ , 6,474.0 keV ] > ²¹⁶Th													3.850'332	%	²⁰⁰Hg	0.000'132	%	²⁰⁸Pb
Isotope_091_pa_217_u	Unstable	²¹⁷Pa	Fermion	91	p	126	n	9/2	-1	217.018'323'986'0	u	~ 0	%	~ 0	17.800'445'000'0	MeV	7.659'308'000'0	MeV	-		-		1.10E-10	year	3.480	milli-seconds ( x⁻³ )	100.000'000	%	α	8,488.790	keV	²¹³Ac	²¹⁷Pa > [ 100 % , α , 8,488.79 keV ] > ²¹³Ac																		?	%	²⁰⁵Tl	?	%	²⁰¹Hg	?	%	¹⁹⁷Au
Isotope_091_pa_218_u	Unstable	²¹⁸Pa	Boson	91	p	127	n	?	0	218.020'041'889'0	u	~ 0	%	~ 0	17.068'683'000'0	MeV	7.664'579'000'0	MeV	-		-		3.58E-12	year	113.000	micro-seconds ( x⁻⁶ )	100.000'000	%	α	9,815.000	keV	²¹⁴Ac	²¹⁸Pa > [ 100 % , α , 9,815.0 keV ] > ²¹⁴Ac																		92.344'731	%	²⁰⁶Pb	5.797'770	%	²⁰²Hg	0.057'978	%	¹⁹⁸Hg
Isotope_091_pa_219_u	Unstable	²¹⁹Pa	Fermion	91	p	128	n	9/2	-1	219.019'883'143'0	u	~ 0	%	~ 0	18.668'900'000'0	MeV	7.659'104'000'0	MeV	-		-		1.68E-15	year	53.000	nano-seconds ( x⁻⁹ )	100.000'000	%	α	10,084.600	keV	²¹⁶Ac	²¹⁹Pa > [ 100 % , α , 10,084.6 keV ] > ²¹⁶Ac	β+	3,026.300	keV	²¹⁹Th	²¹⁹Pa > [ , β+ , 3,026.3 keV ] > ²¹⁹Th													93.210'000	%	²⁰⁷Pb	6.896'511	%	²⁰³Tl	0.000'001	%	¹⁹⁹Hg
Isotope_091_pa_220_u	Unstable	²²⁰Pa	Boson	91	p	129	n	1	-1	220.021'875'303'0	u	~ 0	%	~ 0	18.521'029'000'0	MeV	7.661'662'000'0	MeV	-		-		2.47E-14	year	780.000	nano-seconds ( x⁻⁹ )	100.000'000	%	α	9,829.100	keV	²¹⁶Ac	²²⁰Pa > [ 100 % , α , 9,829.1 keV ] > ²¹⁶Ac	β+	4,685.600	keV	²²⁰Th	²²⁰Pa > [ , β+ , 4,685.6 keV ] > ²²⁰Th													0.002'225	%	²⁰⁸Pb	?	%	²⁰⁰Hg
Isotope_091_pa_221_u	Unstable	²²¹Pa	Fermion	91	p	130	n	9/2	-1	221.021'877'983'0	u	~ 0	%	~ 0	20.376'714'000'0	MeV	7.655'089'000'0	MeV	-		-		1.87E-16	year	5.900	nano-seconds ( x⁻⁹ )	100.000'000	%	α	9,247.700	keV	²¹⁷Ac	²²¹Pa > [ 100 % , α , 9,247.7 keV ] > ²¹⁷Ac																		100.460'820	%	²⁰⁵Tl
Isotope_091_pa_222_u	Unstable	²²²Pa	Boson	91	p	131	n	?	0	222.023'742'000'0	u	~ 0	%	~ 0	20.379'211'000'0	MeV	7.656'961'000'0	MeV	-		-		1.01E-10	year	3.200	milli-seconds ( x⁻³ )	100.000'000	%	α	8,847.000	keV	²¹⁸Ac	²²²Pa > [ 100 % , α , 8,847.0 keV ] > ²¹⁸Ac																		100.175'000	%	²⁰⁶Pb
Isotope_091_pa_223_u	Unstable	²²³Pa	Fermion	91	p	132	n	9/2	-1	223.023'962'273'0	u	~ 0	%	~ 0	22.116'000'000'0	MeV	7.651'000'000'0	MeV	-		-		1.62E-10	year	5.100	milli-seconds ( x⁻³ )	100.000'000	%	α	8,326.300	keV	²¹⁹Ac	²²³Pa > [ 100 % , α , 8,326.3 keV ] > ²¹⁹Ac	β+	1,912.800	keV	²²³Th	²²³Pa > [ , β+ , 1,912.8 keV ] > ²²³Th													100.001'001	%	²⁰⁷Pb
Isotope_091_pa_224_u	Unstable	²²⁴Pa	Boson	91	p	133	n	5	-1	224.025'625'738'0	u	~ 0	%	~ 0	22.320'714'000'0	MeV	7.651'971'000'0	MeV	-		-		2.67E-8	year	844.000	milli-seconds ( x⁻³ )	100.000'000	%	α	7,693.680	keV	²²⁰Ac	²²⁴Pa > [ 100 % , α , 7,693.68 keV ] > ²²⁰Ac	β+	2,851.700	keV	²²⁴Th	²²⁴Pa > [ , β+ , 2,851.7 keV ] > ²²⁴Th													100.130'500	%	²⁰⁸Pb	?	%	²⁰⁶Pb	?	%	²⁰⁰Hg
Isotope_091_pa_225_u	Unstable	²²⁵Pa	Fermion	91	p	134	n	5/2	-1	225.026'130'678'0	u	~ 0	%	~ 0	23.870'222'000'0	MeV	7.646'925'000'0	MeV	-		-		5.39E-8	year	1.700	seconds ( x⁰ )	100.000'000	%	α	7,392.500	keV	²²¹Ac	²²⁵Pa > [ 100 % , α , 7,392.5 keV ] > ²²¹Ac																		100.000'000	%	²⁰⁵Tl
Isotope_091_pa_226_u	Unstable	²²⁶Pa	Boson	91	p	135	n	?	0	226.027'947'753'0	u	~ 0	%	~ 0	24.340'570'000'0	MeV	7.646'721'000'0	MeV	-		-		3.49E-6	year	109.980	seconds ( x⁰ )	74.000'000	%	α	9,686.800	keV	²²²Ac	²²⁶Pa > [ 74 % , α , 9,686.8 keV ] > ²²²Ac	β+	1,813.900	keV	²²⁶Th	²²⁶Pa > [ , β+ , 1,813.9 keV ] > ²²⁶Th													100.000'133	%	²⁰⁶Pb	0.000'000	%	²⁰⁸Pb
Isotope_091_pa_227_u	Unstable	²²⁷Pa	Fermion	91	p	136	n	5/2	-1	227.028'805'072'0	u	~ 0	%	~ 0	26.033'165'000'0	MeV	7.641'110'000'0	MeV	-		-		7.29E-5	year	2.300	kilo-seconds ( x³ )	85.000'000	%	α	6,580.400	keV	²²³Ac	²²⁷Pa > [ 85 % , α , 6,580.4 keV ] > ²²³Ac	ϵ	1,025.580	keV	²²⁷Th	²²⁷Pa > [ , ϵ , 1,025.58 keV ] > ²²⁷Th													100.276'037	%	²⁰⁷Pb	0.000'000	%	²⁰⁵Tl
Isotope_091_pa_228_u	Unstable	²²⁸Pa	Boson	91	p	137	n	3	1	228.031'051'376'0	u	~ 0	%	~ 0	26.831'753'000'0	MeV	7.639'488'000'0	MeV	3.480'000'000'0	nm	-		2.50E-3	year	78.970	kilo-seconds ( x³ )	98.000'000	%	β+	1,129.780	keV	²²⁸Th	²²⁸Pa > [ 98 % , β+ , 1,129.78 keV ] > ²²⁸Th	α	6,264.540	keV	²²⁴Ac	²²⁸Pa > [ , α , 6,264.54 keV ] > ²²⁴Ac													100.036'669	%	²⁰⁸Pb	0.000'000	%	²⁰⁶Pb
Isotope_091_pa_229_u	Unstable	²²⁹Pa	Fermion	91	p	138	n	5/2	1	229.032'096'793'0	u	~ 0	%	~ 0	28.924'171'000'0	MeV	7.632'204'000'0	MeV	-		-		4.11E-3	year	129.600	kilo-seconds ( x³ )	100.000'000	%	ϵ	311.460	keV	²²⁹Th	²²⁹Pa > [ 100 % , ϵ , 311.46 keV ] > ²²⁹Th	α	5,834.840	keV	²²⁵Ac	²²⁹Pa > [ , α , 5,834.84 keV ] > ²²⁵Ac													100.492'861	%	²⁰⁵Tl	0.000'000	%	²⁰⁷Pb
Isotope_091_pa_230_u	Unstable	²³⁰Pa	Boson	91	p	139	n	2	-1	230.034'540'754'0	u	~ 0	%	~ 0	29.897'971'000'0	MeV	7.629'869'000'0	MeV	2.000'000'000'0	nm	-		4.76E-2	year	1.503	mega-seconds ( x⁶ )	91.600'000	%	β+	288.330	keV	²³⁰Th	²³⁰Pa > [ 91.6 % , β+ , 288.33 keV ] > ²³⁰Th	β-	559.800	keV	²³⁰U	²³⁰Pa > [ , β- , 559.8 keV ] > ²³⁰U	0.003'200	%	α	5,439.380	keV	²²⁶Ac	²³⁰Pa > [ 0.0032 % , α , 5,439.38 keV ] > ²²⁶Ac						100.043'661	%	²⁰⁶Pb	0.000'002	%	²⁰⁵Tl	0.000'000	%	²⁰⁸Pb
Isotope_091_pa_231_u	Unstable	²³¹Pa	Fermion	91	p	140	n	3/2	-1	231.035'883'990'0	u	~ 0	%	~ 0	32.174'506'000'0	MeV	7.622'7.622'7.622'7.622	MeV	2.100'000'000'0	nm	-		3.28E+4	years	1.035	tera-seconds ( x¹² )	100.000'000	%	α	5,149.870	keV	²²⁷Ac	²³¹Pa > [ 100 % , α , 5,149.87 keV ] > ²²⁷Ac	²⁴Ne	?	keV	²⁰⁷Tl	²³¹Pa > [ , ²⁴Ne , ? keV ] > ²⁰⁷Tl	0.000'000	%	SF	?	keV	V	²³¹Pa > [ 0.0000000003 % , SF , ? keV ] > V	0.000'000	%	²³F	?	keV	100.276'314	%	²⁰⁷Pb	0.000'000	%	²⁰⁵Tl	0.000'000	%	²⁰⁸Pb
Isotope_091_pa_232_u	Unstable	²³²Pa	Boson	91	p	141	n	2	-1	232.038'591'592'0	u	~ 0	%	~ 0	33.425'722'000'0	MeV	7.618'420'000'0	MeV	-		-1.720'000'000'0	b	3.58E-3	year	113.011	kilo-seconds ( x³ )	100.000'000	%	β-	1,337.100	keV	²³²U	²³²Pa > [ 100 % , β- , 1,337.1 keV ] > ²³²U	ϵ	499.530	keV	²³²Th	²³²Pa > [ , ϵ , 499.53 keV ] > ²³²Th													100.007'000	%	²⁰⁸Pb	0.000'000	%	²⁰⁶Pb	?	%	²⁰⁰Hg
Isotope_091_pa_233_u	Unstable	²³³Pa	Fermion	91	p	142	n	3/2	-1	233.040'247'277'0	u	~ 0	%	~ 0	35.947'837'000'0	MeV	7.609'501'000'0	MeV	3.390'000'000'0	nm	-		7.38E-2	year	2.330	mega-seconds ( x⁶ )	100.000'000	%	β-	570.140	keV	²³³U	²³³Pa > [ 100 % , β- , 570.14 keV ] > ²³³U																		100.012'800	%	²⁰⁵Tl	0.000'000	%	²⁰⁷Pb
Isotope_091_pa_234_u	Unstable	²³⁴Pa	Boson	91	p	143	n	4	1	234.043'308'058'0	u	~ 0	%	~ 0	37.490'098'000'0	MeV	7.604'864'000'0	MeV	-		-3.000'000'000'0	b	7.61E-4	year	24.012	kilo-seconds ( x³ )	100.000'000	%	β-	2,194.570	keV	²³⁴U	²³⁴Pa > [ 100 % , β- , 2,194.57 keV ] > ²³⁴U	SF	?	keV	V	²³⁴Pa > [ , SF , ? keV ] > V													100.044'159	%	²⁰⁶Pb	0.000'002	%	²⁰⁵Tl	0.000'000	%	²⁰⁸Pb
Isotope_091_pa_235_u	Unstable	²³⁵Pa	Fermion	91	p	144	n	3/2	-1	235.045'443'615'0	u	~ 0	%	~ 0	40.341'197'000'0	MeV	7.594'673'000'0	MeV	-		-		4.65E-5	year	1.466	kilo-seconds ( x³ )	100.000'000	%	β-	1,410.000	keV	²³⁵U	²³⁵Pa > [ 100 % , β- , 1,410.0 keV ] > ²³⁵U																		100.276'314	%	²⁰⁷Pb	0.000'000	%	²⁰⁵Tl	0.000'000	%	²⁰⁶Pb	?	%	¹⁸⁰Hf
Isotope_091_pa_236_u	Unstable	²³⁶Pa	Boson	91	p	145	n	1	-1	236.048'681'284'0	u	~ 0	%	~ 0	42.330'456'000'0	MeV	7.588'236'000'0	MeV	-		-		1.74E-5	year	550.020	seconds ( x⁰ )	100.000'000	%	β-	2,900.000	keV	²³⁶U	²³⁶Pa > [ 100 % , β- , 2,900.0 keV ] > ²³⁶U	β-SF	?	keV	V	²³⁶Pa > [ , β-SF , ? keV ] > V													100.004'000	%	²⁰⁸Pb	0.000'000	%	²⁰⁶Pb	?	%	²⁰⁰Hg	0.000'000	%	²⁰⁸Pb
Isotope_091_pa_237_u	Unstable	²³⁷Pa	Fermion	91	p	146	n	1/2	1	237.051'145'659'0	u	~ 0	%	~ 0	45.346'325'000'0	MeV	7.577'504'000'0	MeV	-		-		1.65E-5	year	520.020	seconds ( x⁰ )	100.000'000	%	β-	2,250.000	keV	²³⁷U	²³⁷Pa > [ 100 % , β- , 2,250.0 keV ] > ²³⁷U																		100.012'800	%	²⁰⁵Tl	0.000'000	%	²⁰⁷Pb
Isotope_091_pa_238_u	Unstable	²³⁸Pa	Boson	91	p	147	n	3	-1	238.054'502'710'0	u	~ 0	%	~ 0	47.641'875'000'0	MeV	7.569'902'000'0	MeV	-		-		4.31E-6	year	136.020	seconds ( x⁰ )	100.000'000	%	β-	3,460.000	keV	²³⁸U	²³⁸Pa > [ 100 % , β- , 3,460.0 keV ] > ²³⁸U	β-SF	?	keV	V	²³⁸Pa > [ , β-SF , ? keV ] > V													100.044'159	%	²⁰⁶Pb	0.000'002	%	²⁰⁵Tl	0.000'000	%	²⁰⁸Pb
Isotope_091_pa_239_u	Unstable	²³⁹Pa	Fermion	91	p	148	n	3/2	-1	239.057'260'000'0	u	~ 0	%	~ 0	50.768'948'000'0	MeV	7.558'870'000'0	MeV	-		-		2.06E-4	year	6.516	kilo-seconds ( x³ )	100.000'000	%	β-	2,763.000	keV	²³⁹U	²³⁹Pa > [ 100 % , β- , 2,763.0 keV ] > ²³⁹U																		100.276'314	%	²⁰⁷Pb	0.000'000	%	²⁰⁵Tl	0.000'000	%	²⁰⁶Pb	0.000'000	%	¹⁶⁰Dy	0.000'000	%	¹⁴⁰Ce	?	%	¹⁷²Yb	?	%	¹⁷⁶Hf	?	%	¹⁵²Sm	?	%	¹⁸⁰Hf	?	%	¹⁵⁶Gd	?	%	¹⁶⁸Er	?	%	¹⁶⁴Dy
Isotope_091_pa_240_u	Unstable	²⁴⁰Pa	Boson	91	p	149	n	?	0	240.060'980'000'0	u	~ 0	%	~ 0	53.337'000'000'0	MeV	7.550'000'000'0	MeV	-		-		3.18E-6	year	100.200	seconds ( x⁰ )	?	%	β-	4,087.000	keV	²⁴⁰U	²⁴⁰Pa > [ ? % , β- , 4,087.0 keV ] > ²⁴⁰U																		?	%	²⁰⁸Pb	?	%	²⁰⁶Pb	?	%	²⁰⁰Hg	0.000'000	%	²⁰⁸Pb

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