Iodine (I)

Iodine is the 53rd element in the periodic table and has a symbol of I and atomic number of 53. It has an atomic weight of 126.90447 and a mass number of 127. Iodine has fifty-three protons and seventy-four neutrons in its nucleus, and fifty-three electrons in five shells. It is located in group seventeen, period five and block p of the periodic table. Dark violet nonmetallic element, belongs to group 17 of the periodic table. Insoluble in water. Required as a trace element for living organisms. One stable isotope, I-127 exists, in addition to fourteen radioactive isotopes. Chemically the least reactive of the halogens, and the most electropositive metallic halogen. Discovered in 1812 by Courtois.

Atomic Number	53
Atomic Weight	126.90447
Mass Number	127

Group	17
Period	5
Block	p

Protons	53 p⁺
Neutrons	74 n⁰
Electrons	53 e^-

Physical Properties

Atomic Radius	140 pm 238 pm
Molar Volume	25.7 cm³/mol
Covalent Radius	133 pm 129 pm 125 pm 140 pm 139 pm
Metallic Radius	139 pm
Ionic Radius	220 pm 44 pm 95 pm 42 pm 53 pm
Crystal Radius	206 pm 58 pm 109 pm 56 pm 67 pm
Van der Waals Radius	210 pm 198 pm 415 pm 198 pm 236 pm 203 pm 450 pm
Density	4.933 g/cm³

Chemical Properties

Energy

Proton Affinity	608.2 kJ/mol
Electron Affinity	3.0590368 eV/particle
Ionization Energy	10.45126 eV/particle 19.13126 eV/particle 29.57 eV/particle 40.36 eV/particle 51.517 eV/particle 74.37 eV/particle 87.61 eV/particle 150.81 eV/particle 171 eV/particle 197 eV/particle 220.9 eV/particle 247 eV/particle 279 eV/particle 307 eV/particle 335 eV/particle 365 eV/particle 393 eV/particle 505 eV/particle 535 eV/particle 569 eV/particle 601 eV/particle 649 eV/particle 683 eV/particle 762 eV/particle 800.76 eV/particle 1,397 eV/particle 1,472 eV/particle 1,553 eV/particle 1,639 eV/particle 1,720 eV/particle 1,812 eV/particle 1,911 eV/particle 1,999 eV/particle 2,093 eV/particle 2,181 eV/particle 2,431 eV/particle 2,510 eV/particle 2,598 eV/particle 2,680 eV/particle 2,836 eV/particle 2,930 eV/particle 3,096 eV/particle 3,185.5 eV/particle 7,337 eV/particle 7,600 eV/particle 7,800 eV/particle 8,044 eV/particle 8,601 eV/particle 8,867 eV/particle 9,196 eV/particle 9,421.1 eV/particle 38,716.994 eV/particle 39,721.41 eV/particle

Heat of Vaporization	41.95 kJ/mol
Heat of Fusion	15.52 kJ/mol
Heat of Formation	106.757 kJ/mol
Electrons

Electron Shells	2, 8, 18, 18, 7

Valence Electrons	7 ⓘ

Electron Configuration	[Kr] 4d¹⁰ 5s² 5p⁵ⓘ 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 4d¹⁰ 5s² 5p⁵

Oxidation States	-1, 1, 2, 3, 4, 5, 6, 7
Electronegativity	13.95 eV/particle 0.2195176 2.66
Electrophilicity Index	3.0864889135126865 eV/particle
States of Matter

Phase	Solid
Gas Phase
Boiling Point	457.55 K
Melting Point	386.85 K
Critical Pressure
Critical Temperature	819.15 K
Triple Point	386.75 K 12.11 kPa
Visual
Iodine is a Slate Gray. I has a CPK of #a020f0, Jmol of #940094, and MOLCAS GV of #940094. The Appearance of Element 53 is lustrous metallic gray, violet as a gas.
Color	Slate Gray #a020f0 #940094 #940094
Appearance	lustrous metallic gray, violet as a gas
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
Molar Heat Capacity	54.43 J/(mol K)
Specific Heat Capacity	0.214 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
Type	Insulator
Electrical Conductivity	0.0000000000001 MS/m
Electrical Resistivity	10,000,000 Ω*m
Superconducting Point
Magnetism
Type	diamagnetic
Magnetic Susceptibility (Mass)	-0.0000000045 m³/Kg
Magnetic Susceptibility (Molar)	-0.00000000114 m³/mol
Magnetic Susceptibility (Volume)	-0.0000222
Magnetic Ordering
Curie Point
Neel Point
Structure
The Crystal Structure of Iodine is ORC. The lattice constant of I is 7.72 Å. The lattice angles of Element 53 are π/2, π/2, π/2.
Crystal Structure	Base Centered Orthorhombic (ORC)
Lattice Constant	7.72 Å
Lattice Angles	π/2, π/2, π/2
Mechanical Properties
The Bulk Modulus of Iodine is 7.7 GPa.
Hardness
Bulk Modulus	7.7 GPa
Shear Modulus
Young's Modulus
Poisson Ratio
Speed of Sound
Classification
The CAS Group of Iodine is VIIB. The IUPAC Group of I is VIIA. The Glawe Number of Element 53 is 99. The Mendeleev Number of Iodine (I) is 109. The Pettifor Number of Iodine is 97. The Geochemical Class of I is semi-volatile. The Goldschmidt Class of Element 53 is litophile.
Category	Halogens, Halogens
CAS Group	VIIB
IUPAC Group	VIIA
Glawe Number	99
Mendeleev Number	109
Pettifor Number	97
Geochemical Class	semi-volatile
Goldschmidt Class	litophile

Other

The Gas Basicity of Iodine is 583.5 kJ/mol. The Dipole Polarizability of I is 32.9 plus or minus 1.3 a₀. Element 53 has a C6 Dispersion Coefficient (CD) of 385 a₀, and C6 Dispersion Coefficient (GB) of 389 a₀. The Allotropes of Iodine (I) is Diiodine. The Neutron Cross Section of Iodine is 6.3. The Neutron Mass Absorption of I is 0.0018. The Quantum Numbers of Element 53 is 2P3/2. The Space Group of Iodine (I) is 64 (Cmca).

Gas Basicity	583.5 kJ/mol
Dipole Polarizability	32.9 ± 1.3 a₀
C6 Dispersion Coefficient	385 a₀ 389 a₀
Allotropes	Diiodine
Neutron Cross Section	6.3
Neutron Mass Absorption	0.0018
Quantum Numbers	2P3/2
Space Group	64 (Cmca)

Isotopes of Iodine

Stable Isotopes	1
Unstable Isotopes	41
Natural Isotopes	1

¹⁰⁶I

Mass Number	106
Neutron Number	53
Relative Atomic Mass	105.953516 ± 0.000429 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

Decay Mode	Intensity
α (α emission)

¹⁰⁷I

Mass Number	107
Neutron Number	54
Relative Atomic Mass	106.946935 ± 0.000322 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life
Spin	5/2
Quadrupole Moment
Discovery Year
Parity	+

Decay Mode	Intensity
α (α emission)

¹⁰⁸I

Mass Number	108
Neutron Number	55
Relative Atomic Mass	107.943348 ± 0.000109 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	26.4 ± 0.8 ms
Spin	1
Quadrupole Moment
Discovery Year	1991
Parity	+

Decay Mode	Intensity
α (α emission)	99.5%
p (proton emission)	0.5%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
β⁺ p (β⁺-delayed proton emission)

¹⁰⁹I

Mass Number	109
Neutron Number	56
Relative Atomic Mass	108.938086022 ± 0.000007223 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	92.8 ± 0.8 us
Spin	1/2
Quadrupole Moment	0
Discovery Year	1984
Parity	+

Decay Mode	Intensity
p (proton emission)	99.986%
α (α emission)	0.014%

¹¹⁰I

Mass Number	110
Neutron Number	57
Relative Atomic Mass	109.935085102 ± 0.000066494 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	664 ± 24 ms
Spin	1
Quadrupole Moment
Discovery Year	1977
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	83%
α (α emission)	17%
β⁺ p (β⁺-delayed proton emission)	11%
β⁺α (β⁺-delayed α emission)	1.1%

¹¹¹I

Mass Number	111
Neutron Number	58
Relative Atomic Mass	110.930269236 ± 0.000005103 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.5 ± 0.2 s
Spin	5/2
Quadrupole Moment
Discovery Year	1977
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	0.088%
β⁺ p (β⁺-delayed proton emission)

¹¹²I

Mass Number	112
Neutron Number	59
Relative Atomic Mass	111.928004548 ± 0.000011 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	3.34 ± 0.08 s
Spin	1
Quadrupole Moment
Discovery Year	1977
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	0.0012%
β⁺ p (β⁺-delayed proton emission)	0.88%
β⁺α (β⁺-delayed α emission)	0.104%

¹¹³I

Mass Number	113
Neutron Number	60
Relative Atomic Mass	112.923650062 ± 0.0000086 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	6.6 ± 0.2 s
Spin	5/2
Quadrupole Moment
Discovery Year	1977
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	3.31%
β⁺α (β⁺-delayed α emission)

¹¹⁴I

Mass Number	114
Neutron Number	61
Relative Atomic Mass	113.9220189 ± 0.0000215 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.01 ± 0.15 s
Spin	1
Quadrupole Moment
Discovery Year	1977
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)
α (α emission)	7.7%

¹¹⁵I

Mass Number	115
Neutron Number	62
Relative Atomic Mass	114.918048 ± 0.000031 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	1.3 ± 0.2 m
Spin	5/2
Quadrupole Moment
Discovery Year	1969
Parity	+

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

¹¹⁶I

Mass Number	116
Neutron Number	63
Relative Atomic Mass	115.916885513 ± 0.000080555 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.91 ± 0.15 s
Spin	1
Quadrupole Moment
Discovery Year	1976
Parity	+

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

¹¹⁷I

Mass Number	117
Neutron Number	64
Relative Atomic Mass	116.913645649 ± 0.000027437 Da
G-Factor	1.24 ± 0.08
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.22 ± 0.04 m
Spin	5/2
Quadrupole Moment
Discovery Year	1969
Parity

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
e⁺ (positron emission)	77%

¹¹⁸I

Mass Number	118
Neutron Number	65
Relative Atomic Mass	117.913074 ± 0.000021213 Da
G-Factor	1 ± 0.1
Abundance
Radioactivity	☢️ Radioactive
Half Life	13.7 ± 0.5 m
Spin	2
Quadrupole Moment
Discovery Year	1957
Parity	-

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

¹¹⁹I

Mass Number	119
Neutron Number	66
Relative Atomic Mass	118.91006091 ± 0.000023302 Da
G-Factor	1.16 ± 0.04
Abundance
Radioactivity	☢️ Radioactive
Half Life	19.1 ± 0.4 m
Spin	5/2
Quadrupole Moment
Discovery Year	1954
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
e⁺ (positron emission)	51%
ϵ (electron capture)	49%

¹²⁰I

Mass Number	120
Neutron Number	67
Relative Atomic Mass	119.910093729 ± 0.000016212 Da
G-Factor	0.615 ± 0.015
Abundance
Radioactivity	☢️ Radioactive
Half Life	81.67 ± 0.18 m
Spin	2
Quadrupole Moment
Discovery Year	1957
Parity	-

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

¹²¹I

Mass Number	121
Neutron Number	68
Relative Atomic Mass	120.907411492 ± 0.00000507 Da
G-Factor	0.92 ± 0.04
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.12 ± 0.01 h
Spin	5/2
Quadrupole Moment
Discovery Year	1950
Parity	+

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

¹²²I

Mass Number	122
Neutron Number	69
Relative Atomic Mass	121.907590094 ± 0.000005561 Da
G-Factor	0.94 ± 0.03
Abundance
Radioactivity	☢️ Radioactive
Half Life	3.63 ± 0.06 m
Spin	1
Quadrupole Moment
Discovery Year	1950
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
e⁺ (positron emission)	78%
ϵ (electron capture)	22%

¹²³I

Mass Number	123
Neutron Number	70
Relative Atomic Mass	122.905589753 ± 0.000003956 Da
G-Factor	1.1272 ± 0.0028
Abundance
Radioactivity	☢️ Radioactive
Half Life	13.2232 ± 0.0015 h
Spin	5/2
Quadrupole Moment
Discovery Year	1949
Parity	+

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

¹²⁴I

Mass Number	124
Neutron Number	71
Relative Atomic Mass	123.906210297 ± 0.000002467 Da
G-Factor	0.723 ± 0.002
Abundance
Radioactivity	☢️ Radioactive
Half Life	4.176 ± 0.0003 d
Spin	2
Quadrupole Moment
Discovery Year	1938
Parity	-

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

¹²⁵I

Mass Number	125
Neutron Number	72
Relative Atomic Mass	124.90463061 ± 0.000001452 Da
G-Factor	1.1284 ± 0.002
Abundance
Radioactivity	☢️ Radioactive
Half Life	59.392 ± 0.008 d
Spin	5/2
Quadrupole Moment	-0.752 ± 0.017
Discovery Year	1947
Parity	+

Decay Mode	Intensity
ϵ (electron capture)	100%

¹²⁶I

Mass Number	126
Neutron Number	73
Relative Atomic Mass	125.905624205 ± 0.000004055 Da
G-Factor	0.719 ± 0.002
Abundance
Radioactivity	☢️ Radioactive
Half Life	12.93 ± 0.05 d
Spin	2
Quadrupole Moment
Discovery Year	1938
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	52.7%
β⁻ (β⁻ decay)	47.3%

¹²⁷I

Mass Number	127
Neutron Number	74
Relative Atomic Mass	126.904472592 ± 0.000003887 Da
G-Factor
Abundance	100
Radioactivity	Stable
Half Life	Not Radioactive ☢️
Spin	5/2
Quadrupole Moment	-0.688 ± 0.01
Discovery Year	1920
Parity	+

¹²⁸I

Mass Number	128
Neutron Number	75
Relative Atomic Mass	127.905809355 ± 0.000003887 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	24.99 ± 0.02 m
Spin	1
Quadrupole Moment
Discovery Year	1934
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	93.1%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	6.9%

¹²⁹I

Mass Number	129
Neutron Number	76
Relative Atomic Mass	128.904983643 ± 0.000003385 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	16.14 ± 0.12 My
Spin	7/2
Quadrupole Moment
Discovery Year	1951
Parity	+

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

¹³⁰I

Mass Number	130
Neutron Number	77
Relative Atomic Mass	129.906670168 ± 0.000003385 Da
G-Factor	0.6698 ± 0.0014
Abundance
Radioactivity	☢️ Radioactive
Half Life	12.36 ± 0.01 h
Spin	5
Quadrupole Moment
Discovery Year	1938
Parity	+

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

¹³¹I

Mass Number	131
Neutron Number	78
Relative Atomic Mass	130.906126375 ± 0.000000649 Da
G-Factor	0.78228571428571 ± 0.00028571428571429
Abundance
Radioactivity	☢️ Radioactive
Half Life	8.0249 ± 0.0006 d
Spin	7/2
Quadrupole Moment	-0.34 ± 0.02
Discovery Year	1939
Parity	+

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

¹³²I

Mass Number	132
Neutron Number	79
Relative Atomic Mass	131.907993511 ± 0.000004364 Da
G-Factor	0.772 ± 0.00175
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.295 ± 0.013 h
Spin	4
Quadrupole Moment	0.08 ± 0.01
Discovery Year	1948
Parity	+

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

¹³³I

Mass Number	133
Neutron Number	80
Relative Atomic Mass	132.9078284 ± 0.000006335 Da
G-Factor	0.816 ± 0.0014285714285714
Abundance
Radioactivity	☢️ Radioactive
Half Life	20.83 ± 0.08 h
Spin	7/2
Quadrupole Moment	-0.23 ± 0.01
Discovery Year	1940
Parity	+

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

¹³⁴I

Mass Number	134
Neutron Number	81
Relative Atomic Mass	133.90977566 ± 0.000005213 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	52.5 ± 0.2 m
Spin	4
Quadrupole Moment
Discovery Year	1948
Parity

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

¹³⁵I

Mass Number	135
Neutron Number	82
Relative Atomic Mass	134.910059355 ± 0.000002211 Da
G-Factor	0.84 ± 0.00057142857142857
Abundance
Radioactivity	☢️ Radioactive
Half Life	6.58 ± 0.03 h
Spin	7/2
Quadrupole Moment
Discovery Year	1940
Parity	+

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

¹³⁶I

Mass Number	136
Neutron Number	83
Relative Atomic Mass	135.914604693 ± 0.000015231 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	83.4 ± 0.4 s
Spin	1
Quadrupole Moment
Discovery Year	1949
Parity	-

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

¹³⁷I

Mass Number	137
Neutron Number	84
Relative Atomic Mass	136.918028178 ± 0.000009 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	24.13 ± 0.12 s
Spin	7/2
Quadrupole Moment
Discovery Year	1943
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	7.51%

¹³⁸I

Mass Number	138
Neutron Number	85
Relative Atomic Mass	137.922726392 ± 0.0000064 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	6.26 ± 0.03 s
Spin	1
Quadrupole Moment
Discovery Year	1949
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	5.33%

¹³⁹I

Mass Number	139
Neutron Number	86
Relative Atomic Mass	138.9264934 ± 0.0000043 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.28 ± 0.011 s
Spin	7/2
Quadrupole Moment
Discovery Year	1949
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	9.74%

¹⁴⁰I

Mass Number	140
Neutron Number	87
Relative Atomic Mass	139.931715914 ± 0.000013 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	588 ± 10 ms
Spin	2
Quadrupole Moment
Discovery Year	1972
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	7.6%
2n (2-neutron emission)

¹⁴¹I

Mass Number	141
Neutron Number	88
Relative Atomic Mass	140.935666081 ± 0.000017 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	420 ± 7 ms
Spin	7/2
Quadrupole Moment
Discovery Year	1974
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	21.2%

¹⁴²I

Mass Number	142
Neutron Number	89
Relative Atomic Mass	141.941166595 ± 0.0000053 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	235 ± 11 ms
Spin	2
Quadrupole Moment
Discovery Year	1975
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

¹⁴³I

Mass Number	143
Neutron Number	90
Relative Atomic Mass	142.945475 ± 0.000215 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	182 ± 8 ms
Spin	7/2
Quadrupole Moment
Discovery Year	1994
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

¹⁴⁴I

Mass Number	144
Neutron Number	91
Relative Atomic Mass	143.951336 ± 0.000429 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	94 ± 8 ms
Spin	1
Quadrupole Moment
Discovery Year	1994
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

¹⁴⁵I

Mass Number	145
Neutron Number	92
Relative Atomic Mass	144.955845 ± 0.000537 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	89.7 ± 9.3 ms
Spin	7/2
Quadrupole Moment
Discovery Year	2010
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

¹⁴⁶I

Mass Number	146
Neutron Number	93
Relative Atomic Mass	145.961846 ± 0.000322 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	94 ± 26 ms
Spin
Quadrupole Moment
Discovery Year	2018
Parity

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

¹⁴⁷I

Mass Number	147
Neutron Number	94
Relative Atomic Mass	146.966505 ± 0.000322 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life
Spin	3/2
Quadrupole Moment
Discovery Year	2018
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

History

Iodine was discovered by French chemist Bernard Courtois in 1811. He treated the liquor obtained from the extraction of kelp, with sulfuric acid to produce a vapour with a violet color. In 1812, Joseph Louis Gay-Lussac demonstrated that iodine was an element and its chemical relationship to chlorine. From the Greek word iodes, violet

Discoverers	Bernard Courtois
Discovery Location	France
Discovery Year	1811
Etymology (Name Origin)	Greek: iôeides (violet colored).
Pronunciation	EYE-eh-dine (English)

Elemental iodine is toxic if taken orally

Kelp was the main source of natural iodine in the 18th and 19th centuries

Uses

Iodine compounds are important in organic chemistry and very useful in medicine. A solution containing potassium iodide and iodine in alcohol is used to disinfect external wounds. Silver iodide is a major ingredient to traditional photographic film. Iodine is added to table salt to prevent thyroid disease. Required in small amounts by humans. Once used as an antiseptic, but no longer due to its poisonous nature.

Sources

Occurs on land and in the sea in sodium and potassium compounds.

Abundance
Abundance in Earth's crust	0.45 mg/kg
Natural Abundance (Oceans)	0.06 mg/L
Natural Abundance (Human Body)	0.00002 %
Natural Abundance (Meteor)	0.000025 %
Natural Abundance (Sun)
Abundance in Universe	0.0000001 %

Nuclear Screening Constants

1	s	1.0609
2	p	4.1526
2	s	13.933
3	d	14.0993
3	p	18.1586
3	s	18.2126
4	d	32.066
4	p	28.9704
4	s	27.7028
5	p	41.3885
5	s	39.5965

Also Known As

I
element 53
53I

Translations

Norwegian Bokmåljod
Frenchiode
Italianiodio
GermanIod
Russianиод
Spanishyodo
Norwegian Nynorskjod
Danishjod
Hungarianjód
Afrikaansjodium
Amharicአዮዲን
AragoneseYodo
Arabicيود
AzerbaijaniYod
BelarusianЁд
Bulgarianйод
Banglaআয়োডিন
BretonIod
Bosnianjod
Catalaniode
CorsicanIodiu
Czechjod
ChuvashИод
WelshÏodin
Divehiއަޔޮޑިން
Greekιώδιο
Esperantojodo
Estonianjood
Basqueiodo
Persianید
Finnishjodi
FriulianJodi
IrishIaidín
GalicianIodo
ManxEeadeen
Hakka ChineseTièn
Hebrewיוד
Hindiआयोडिन
Fiji HindiIodine
CroatianJod
Haitian CreoleYòd
Armenianյոդ
Interlinguaiodo
Indonesianiodin
Idoiodo
Icelandicjoð
Japaneseヨウ素
Lojbanzirkliru
JavaneseYodium
Georgianიოდი
KazakhЙод
Korean아이오딘
KomiЙод
Latiniodum
LuxembourgishIod
LigurianIodio
LithuanianJodas
Latvianjods
Macedonianјод
Malayalamഅയോഡിൻ
Marathiआयोडिन
Western MariИод
Malayiodin
Burmeseအိုင်အိုဒင်း
Low GermanJod
Dutchjodium
OccitanIòde
OsseticЙод
Punjabiਆਇਓਡੀਨ
Polishjod
Western Panjabiآئیوڈین
Portugueseiodo
QuechuaYudu
Romanianiod
Sanskritअयोडिन्
Sicilianjodiu
Serbo-CroatianJod
Slovakjód
SlovenianJod
AlbanianJodi
Serbianјод
Saterland FrisianIod
Swedishjod
SwahiliIodini
Tamilஅயோடின்
Teluguఅయోడిన్
TajikЙод
Thaiไอโอดีน
TagalogYodo
Turkishİyot
Tatarиод
UkrainianЙод
Urduآیوڈین
UzbekYod
VepsJod
Vietnameseiod
WarayYodo
KalmykЙод
Yiddishיאד
YorubaIodine
Chinese碘
CebuanoYodo
Central Kurdishیۆد
Kannadaಅಯೊಡಿನ್
Odiaଆୟୋଡ଼ିନ
Gujaratiઆયોડિન
PiedmonteseJòdio
Scotsiodine
SomaliAaydhiin
Chinese (Hong Kong SAR China)碘
Chinese (China)碘
Cantonese碘
Min Nan ChineseAk-sò͘
ErzyaИод
Belarusian (Taraskievica orthography)ёд
Literary Chinese碘
AromanianIodu
cdoDiēng
FaroeseJod
KyrgyzИод
Nepaliआयोडिन
Newariआयोडिन
LombardIodio
Maltesejodju
AsturianYodu
TuvinianЙод
Scottish GaelicAidhodain
LimburgishJodium
Portuguese (Brazil)iodo
BashkirИод
Paliआयोडिन
Gan Chinese碘
Bhojpuriआयोडीन
azbیود
SundaneseYodium
Tibetanལྦ་ཚྭ།
Tatar (Cyrillic)иод
BislamaAiodin
Zazaİyod
kbpƖyɔdɩ
Mongolianиод
Lingua Franca Novaiodo
oloJoudu
Wu Chinese碘
English (Canada)Iodine
English (United Kingdom)iodine
Northern FrisianJood
Chinese (Traditional)碘
Chinese (Taiwan)碘
Uyghurيود
Chinese (Simplified)碘
SardinianJòdiu
Moroccan Arabicيود
Egyptian Arabicيود
Pashtoآيوډين
lldIodie
BikolIyodo
CornishIodin
BalineseYodium
Malay (Arabic)اييودين
GandaAyodiini
skrآئیوڈین
Korean (North Korea)요드
Skolt Samijood
Inari Samijodi
ZuluInkwithi

Iodine on ChemicalAid

AEDA subject keyword ID	17588
Art & Architecture Thesaurus ID	300380217
Australian Educational Vocabulary ID	scot/3532
BNCF Thesaurus ID	20089
Biblioteca Nacional de España ID	XX529206
Bibliothèque nationale de France ID	11966629x
CAS Registry Number	7553-56-2
ChEBI ID	36897
DeCS ID	7619
Den Store Danske ID	jod
DrugBank ID	05382
Encyclopædia Britannica Online ID	science/iodine
Encyclopædia Universalis ID	iode
Freebase ID	/m/025rw2h
French Vikidia ID	Iode
GND ID	4162271-6
Great Russian Encyclopedia Online ID	2017504
Gujarati Vishwakosh entry	આયોડિન-રસાયણ
Human Metabolome Database ID	HMDB0000675
KBpedia ID	Iodine
KEGG ID	C01382
Krugosvet article	nauka_i_tehnika/himiya/IOD.html
Krugosvet article	nauka_i_tehnika/himiya/IOD_V_PRIRODE.html
Library of Congress authority ID	sh85067769
MeSH descriptor ID	D007455
NALT ID	43370
NDL Authority ID	00574371
NKCR AUT ID	ph425901
NSC number	42355
Namuwiki ID	아이오딘
National Library of Israel J9U ID	987007558171005171
OmegaWiki Defined Meaning	2018
Online PWN Encyclopedia ID	3918052
OpenAlex ID	C539932907
OpenAlex ID	C3017531110
PSH ID	5814
Postimees topic ID	144752
Quora topic ID	Iodine
Spanish Vikidia ID	Yodo
Store medisinske leksikon ID	jod
Store medisinske leksikon ID	jod_-_fysiologiske_egenskaper
Store norske leksikon ID	jod
Treccani ID	iodio
UK Archival Thesaurus ID	f2/mt225/4347/8286/8446
USGS Thesaurus ID	1481
WikiSkripta ID	30611
WordNet 3.1 Synset ID	14665575-n
YSA ID	Y100665
YSO ID	18902
Yle topic ID	18-214695
Zhihu topic ID	19566083

Iodine (I)

Physical Properties

Chemical Properties

Other

Isotopes of Iodine

106I

107I

108I

109I

110I

111I

112I

113I

114I

115I

116I

117I

118I

119I

120I

121I

122I

123I

124I

125I

126I

127I

128I

129I

130I

131I

132I

133I

134I

135I

136I

137I

138I

139I

140I

141I

142I

143I

144I

145I

146I

147I