Fluorine (F)

A poisonous pale yellow gaseous element belonging to group 17 of the periodic table (The halogens). It is the most chemically reactive and electronegative element. It is highly dangerous, causing severe chemical burns on contact with flesh. Fluorine was identified by Scheele in 1771 and first isolated by Moissan in 1886.

Atomic Number	9
Atomic Weight	18.998403163
Mass Number	19

Group	17
Period	2
Block	p

Protons	9 p⁺
Neutrons	10 n⁰
Electrons	9 e^-

Properties

Energy
Atomic Radius	50 pm 163 pm
Molar Volume	17.1 cm³/mol
Covalent Radius	64 pm 59 pm 53 pm 67 pm 57 pm
Metallic Radius
Ionic Radius	128.5 pm 130 pm 131 pm 133 pm 8 pm
Crystal Radius	114.5 pm 116 pm 117 pm 119 pm 22 pm
Van der Waals Radius	150 pm 147 pm 347.2 pm 147 pm 171 pm 146 pm 336.4 pm
Density	0.001553 g/cm³
Proton Affinity	340.1 kJ/mol
Electron Affinity	3.4011897 eV/particle
Ionization Energy	17.42282 eV/particle 34.97081 eV/particle 62.708 eV/particle 87.175 eV/particle 114.249 eV/particle 157.1631 eV/particle 185.1868 eV/particle 953.898 eV/particle 1,103.11743 eV/particle

Heat of Vaporization	6.54 kJ/mol
Heat of Fusion	0.51 kJ/mol
Heat of Formation	79.335 kJ/mol
Electrons
Electron Shells	2, 7

Valence Electrons	7

Electron Configuration	[He] 2s² 2p⁵

Oxidation States	-1, 0
Electronegativity	24.8 eV/particle 0.344443 3.98
Electrophilicity	3.865807423136221 eV/particle
Phases
Phase	Gas
Gas Phase	Diatomic
Boiling Point	85.04 K
Melting Point	53.48 K
Critical Pressure	5.1724 MPa
Critical Temperature	144.41 K
Triple Point	53.48 K 90 kPa
Visual
Color	Colorless #daa520 #90e050 #7fd03b
Appearance
Refractive Index	1.000195
Thermodynamic Properties
Thermal Conductivity	0.028 W/(m K)
Thermal Expansion
Molar Heat Capacity	31.304 J/(mol K)
Specific Heat Capacity	0.824 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)	7/5
Electrical Properties
Type
Electrical Conductivity
Electrical Resistivity
Superconducting Point
Magnetism
Type
Magnetic Susceptibility (Mass)
Magnetic Susceptibility (Molar)
Magnetic Susceptibility (Volume)
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal Structure	Base Centered Monoclinic (MCL)
Lattice Constant
Lattice Angles	π/2, π/2, π/2
Mechanical Properties
Hardness
Bulk Modulus
Shear Modulus
Young Modulus
Poisson Ratio
Speed of Sound
Classification
Category	Halogens, Halogens
CAS Group	VIIB
IUPAC Group	VIIA
Glawe Number	102
Mendeleev Number	106
Pettifor Number	102
Geochemical Class	semi-volatile
Goldschmidt Class	litophile
Other
Gas Basicity	315.1 kJ/mol
Dipole Polarizability	3.74 ± 0.08 a₀
C6 Dispersion Coefficient	9.52 a₀ 10.2 a₀
Allotropes	Difluorine
Neutron Cross Section	0.0096
Neutron Mass Absorption	0.00002
Quantum Numbers	2P3/2
Space Group	15 (C12/c1)

Isotopes of Fluorine

Stable Isotopes	1
Unstable Isotopes	18
Radioactive Isotopes	16

¹³F

Abundance
Relative Atomic Mass	13.045121 ± 0.000537 Da
Mass Number	13
G-Factor
Half Life
Spin	1/2
Quadrupole Moment	0
Discovery Year
Parity	+

¹³F Decay Modes

Decay Mode	Intensity
p (proton emission)	%

¹⁴F

Abundance	Radioactive ☢️
Relative Atomic Mass	14.034315196 ± 0.000044142 Da
Mass Number	14
G-Factor
Half Life	500 ± 60 ys
Spin	2
Quadrupole Moment
Discovery Year	2010
Parity	-

¹⁴F Decay Modes

Decay Mode	Intensity
p (proton emission)	%

¹⁵F

Abundance	Radioactive ☢️
Relative Atomic Mass	15.017785139 ± 0.000015029 Da
Mass Number	15
G-Factor
Half Life	1.1 ± 0.3 zs
Spin	1/2
Quadrupole Moment	0
Discovery Year	1978
Parity	+

¹⁵F Decay Modes

Decay Mode	Intensity
p (proton emission)	100%

¹⁶F

Abundance	Radioactive ☢️
Relative Atomic Mass	16.011460278 ± 0.000005758 Da
Mass Number	16
G-Factor	0
Half Life	21 ± 5 zs
Spin	0
Quadrupole Moment	0
Discovery Year	1964
Parity	-

¹⁶F Decay Modes

Decay Mode	Intensity
p (proton emission)	100%

¹⁷F

Abundance	Radioactive ☢️
Relative Atomic Mass	17.002095237 ± 0.000000266 Da
Mass Number	17
G-Factor	1.88852 ± 0.00012
Half Life	64.37 ± 0.027 s
Spin	5/2
Quadrupole Moment	0.076 ± 0.004
Discovery Year	1934
Parity	+

¹⁷F Decay Modes

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

¹⁸F

Abundance	Radioactive ☢️
Relative Atomic Mass	18.000937324 ± 0.000000497 Da
Mass Number	18
G-Factor
Half Life	109.734 ± 0.008 m
Spin	1
Quadrupole Moment
Discovery Year	1937
Parity	+

¹⁸F Decay Modes

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

¹⁹F

Abundance	100
Relative Atomic Mass	18.99840316207 ± 0.00000000088 Da
Mass Number	19
G-Factor	5.256642 ± 0.000008
Half Life
Spin	1/2
Quadrupole Moment	0
Discovery Year	1920
Parity	+

²⁰F

Abundance	Radioactive ☢️
Relative Atomic Mass	19.999981252 ± 0.000000031 Da
Mass Number	20
G-Factor	1.046675 ± 0.000045
Half Life	11.0062 ± 0.008 s
Spin	2
Quadrupole Moment	0.056 ± 0.004
Discovery Year	1935
Parity	+

²⁰F Decay Modes

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

²¹F

Abundance	Radioactive ☢️
Relative Atomic Mass	20.999948893 ± 0.000001932 Da
Mass Number	21
G-Factor	1.56776 ± 0.00048
Half Life	4.158 ± 0.02 s
Spin	5/2
Quadrupole Moment	0.011 ± 0.002
Discovery Year	1955
Parity	+

²¹F Decay Modes

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

²²F

Abundance	Radioactive ☢️
Relative Atomic Mass	22.002998812 ± 0.00001331 Da
Mass Number	22
G-Factor	0.6736 ± 0.0001
Half Life	4.23 ± 0.04 s
Spin	4
Quadrupole Moment	0.003 ± 0.002
Discovery Year	1965
Parity	+

²²F Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	11%

²³F

Abundance	Radioactive ☢️
Relative Atomic Mass	23.003526875 ± 0.00003577 Da
Mass Number	23
G-Factor
Half Life	2.23 ± 0.14 s
Spin	5/2
Quadrupole Moment
Discovery Year	1970
Parity	+

²³F Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	14%

²⁴F

Abundance	Radioactive ☢️
Relative Atomic Mass	24.00809937 ± 0.000104853 Da
Mass Number	24
G-Factor
Half Life	384 ± 16 ms
Spin	3
Quadrupole Moment
Discovery Year	1970
Parity	+

²⁴F Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	5.9%

²⁵F

Abundance	Radioactive ☢️
Relative Atomic Mass	25.012167727 ± 0.000103535 Da
Mass Number	25
G-Factor
Half Life	80 ± 9 ms
Spin	5/2
Quadrupole Moment
Discovery Year	1970
Parity	+

²⁵F Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	23.1%
2n (2-neutron emission)	%

²⁶F

Abundance	Radioactive ☢️
Relative Atomic Mass	26.020048065 ± 0.000114898 Da
Mass Number	26
G-Factor
Half Life	8.2 ± 0.9 ms
Spin	1
Quadrupole Moment
Discovery Year	1979
Parity	+

²⁶F Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	13.5%
2n (2-neutron emission)	%

²⁷F

Abundance	Radioactive ☢️
Relative Atomic Mass	27.026981897 ± 0.000129037 Da
Mass Number	27
G-Factor
Half Life	5 ± 0.2 ms
Spin	5/2
Quadrupole Moment
Discovery Year	1981
Parity	+

²⁷F Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	77%
2n (2-neutron emission)	%

²⁸F

Abundance	Radioactive ☢️
Relative Atomic Mass	28.035860448 ± 0.000129198 Da
Mass Number	28
G-Factor
Half Life	46 zs
Spin	4
Quadrupole Moment
Discovery Year	2012
Parity	-

²⁸F Decay Modes

Decay Mode	Intensity
n (neutron emission)	100%

²⁹F

Abundance	Radioactive ☢️
Relative Atomic Mass	29.043103 ± 0.000564 Da
Mass Number	29
G-Factor
Half Life	2.5 ± 0.3 ms
Spin	5/2
Quadrupole Moment
Discovery Year	1989
Parity	+

²⁹F Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	60%
2n (2-neutron emission)	%

³⁰F

Abundance
Relative Atomic Mass	30.052561 ± 0.000537 Da
Mass Number	30
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

³⁰F Decay Modes

Decay Mode	Intensity
n (neutron emission)	%

³¹F

Abundance	Radioactive ☢️
Relative Atomic Mass	31.061023 ± 0.000574 Da
Mass Number	31
G-Factor
Half Life
Spin	5/2
Quadrupole Moment
Discovery Year	1999
Parity	+

³¹F Decay Modes

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

History

In 1529, Georigius Agricola described the use of fluorspar as a flux. In 1670 Heinrich Schwandhard found that glass was etched when exposed to fluorspar treated with acid. In 1810, French scientist Andre-Marie Ampere proposed that fluoric acid was a compound of hydrogen with a new element. The element was finally isolated in 1886 by Henri Moissan. From the Latin and French fluere, flow or flux

Discoverers	Henri Moissan
Discovery Location	France
Discovery Year	1886
Etymology (Name Origin)	Latin: fluere (flow).
Pronunciation	FLU-eh-reen (English)

Fluorine is highly toxic and corrosive

Fluorine reacts violently with water to produce oxygen

Uses

Compounds of fluorine, including sodium fluoride, are used in toothpaste and in drinking water to prevent dental cavities. Hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) now serve as replacements for CFC refrigerants. Fluorine and its compounds are used in processing nuclear fuel. Used in refrigerants and other fluorocarbons. Also in toothpaste as sodium fluoride (NaF) and stannous fluoride (SnF2); also in Teflon.

Sources

Found in the minerals fluorite (CaF2) and cryolite(Na3AlF6). Electrolysis of hydrofluoric acid (HF) or potassium acid fluoride (KHF2) is the only practical method of commercial production.

Abundance
Abundance in Earth's crust	585 mg/kg
Abundance in Oceans	1.3 mg/L
Abundance in Human Body	0.0037 %
Abundance in Meteor	0.0087 %
Abundance in Sun	0.00005 %
Abundance in Universe	0.00004 %

Nuclear Screening Constants

1	s	0.3499
2	p	3.9
2	s	3.8724

Fluorine on ChemicalAid

Australian Educational Vocabulary ID	scot/3520
BNCF Thesaurus ID	21008
Biblioteca Nacional de España ID	XX531809
Bibliothèque nationale de France ID	11976289w
Brockhaus Enzyklopädie online ID	fluor
CAS Registry Number	7782-41-4
Den Store Danske ID	fluor
Encyclopædia Britannica Online ID	science/fluorine
Encyclopædia Universalis ID	fluor
Freebase ID	/m/025rqc3
French Vikidia ID	Fluor
GND ID	4017696-4
Great Russian Encyclopedia Online ID	4724787
Italian Vikidia ID	Fluoro
KBpedia ID	Fluorine
Latvian National Encyclopedia Online ID	103880
Library of Congress authority ID	sh85049424
MeSH descriptor ID	D005461
MinDat mineral ID	5396
NALT ID	40726
NKCR AUT ID	ph171329
Namuwiki ID	플루오린
National Diet Library ID	00563785
National Library of Israel J9U ID	987007538444105171
OmegaWiki Defined Meaning	1496
OpenAlex ID	C506198293
PSH ID	5811
Postimees topic ID	580112
PubChem CID	5360525
Quora topic ID	Fluorine
Römpp online ID	RD-06-01350
Spanish Vikidia ID	Flúor
Store medisinske leksikon ID	fluor
Store medisinske leksikon ID	fluor_-_medisin
Store norske leksikon ID	fluor
Treccani ID	fluoro
WikiSkripta ID	30619
YSA ID	Y95172
YSO ID	16439
Yle topic ID	18-12090

Fluorine (F)

Properties

Isotopes of Fluorine

13F

13F Decay Modes

14F

14F Decay Modes

15F

15F Decay Modes

16F

16F Decay Modes

17F

17F Decay Modes

18F

18F Decay Modes

19F

20F

20F Decay Modes

21F

21F Decay Modes

22F

22F Decay Modes

23F

23F Decay Modes

24F

24F Decay Modes

25F

25F Decay Modes

26F

26F Decay Modes

27F

27F Decay Modes

28F

28F Decay Modes

29F

29F Decay Modes

30F

30F Decay Modes

31F

31F Decay Modes