Fluorine

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 Number9
Atomic Weight18.998403163
Mass Number19
Group17
Period2
Blockp
Protons9 p+
Neutrons10 n0
Electrons9 e-
Liquid fluorine tighter crop.jpg Animated Bohr Model of F (Fluorine) Enhanced Bohr Model of F (Fluorine) Bohr Model: F (Fluorine) Orbital Diagram of F (Fluorine)

Properties

Atomic Radius
50 pm
Molar Volume
Covalent Radius
64 pm
Metallic Radius
Ionic Radius
128.5 pm
Crystal Radius
114.5 pm
Van der Waals Radius
147 pm
Density
0.001553 g/cm³
Energy
Proton Affinity
340.1 kJ/mol
Electron Affinity
3.4011897 eV/particle
Ionization Energy
17.42282 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 Shells2, 7
Valence Electrons1
Electron Configuration[He] 2s2 2p5
Oxidation States-1, 0
Electronegativity
3.98
Electrophilicity
3.865807423136221 eV/particle
Phases
PhaseGas
Gas PhaseDiatomic
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
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 StructureBase Centered Monoclinic (MCL)
Lattice Constant
Lattice Anglesπ/2, π/2, π/2
Mechanical Properties
Hardness
Bulk Modulus
Shear Modulus
Young Modulus
Poisson Ratio
Speed of Sound
Classification
CategoryHalogens, Halogens
CAS GroupVIIB
IUPAC GroupVIIA
Glawe Number102
Mendeleev Number106
Pettifor Number102
Geochemical Classsemi-volatile
Goldschmidt Classlitophile
Other
Gas Basicity
315.1 kJ/mol
Dipole Polarizability
3.74 ± 0.08 a₀
C6 Dispersion Coefficient
9.52 a₀
AllotropesDifluorine
Neutron Cross Section
0.0096
Neutron Mass Absorption
0.00002
Quantum Numbers2P3/2
Space Group15 (C12/c1)

Isotopes of Fluorine

Stable Isotopes1
Unstable Isotopes18
Radioactive Isotopes16

13F

Abundance
Relative Atomic Mass
13.045121 ± 0.000537 Da
Mass Number13
G-Factor
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year
Parity+

13F Decay Modes
Decay ModeIntensity
p (proton emission)%

14F

AbundanceRadioactive ☢️
Relative Atomic Mass
14.034315196 ± 0.000044142 Da
Mass Number14
G-Factor
Half Life
500 ± 60 ys
Spin2
Quadrupole Moment
Discovery Year2010
Parity-

14F Decay Modes
Decay ModeIntensity
p (proton emission)%

15F

AbundanceRadioactive ☢️
Relative Atomic Mass
15.017785139 ± 0.000015029 Da
Mass Number15
G-Factor
Half Life
1.1 ± 0.3 zs
Spin1/2
Quadrupole Moment
0
Discovery Year1978
Parity+

15F Decay Modes
Decay ModeIntensity
p (proton emission)100%

16F

AbundanceRadioactive ☢️
Relative Atomic Mass
16.011460278 ± 0.000005758 Da
Mass Number16
G-Factor
0
Half Life
21 ± 5 zs
Spin0
Quadrupole Moment
0
Discovery Year1964
Parity-

16F Decay Modes
Decay ModeIntensity
p (proton emission)100%

17F

AbundanceRadioactive ☢️
Relative Atomic Mass
17.002095237 ± 0.000000266 Da
Mass Number17
G-Factor
1.88852 ± 0.00012
Half Life
64.37 ± 0.027 s
Spin5/2
Quadrupole Moment
0.076 ± 0.004
Discovery Year1934
Parity+

17F Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

18F

AbundanceRadioactive ☢️
Relative Atomic Mass
18.000937324 ± 0.000000497 Da
Mass Number18
G-Factor
Half Life
109.734 ± 0.008 m
Spin1
Quadrupole Moment
Discovery Year1937
Parity+

18F Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

19F

Abundance
100
Relative Atomic Mass
18.99840316207 ± 0.00000000088 Da
Mass Number19
G-Factor
5.256642 ± 0.000008
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year1920
Parity+

20F

AbundanceRadioactive ☢️
Relative Atomic Mass
19.999981252 ± 0.000000031 Da
Mass Number20
G-Factor
1.046675 ± 0.000045
Half Life
11.0062 ± 0.008 s
Spin2
Quadrupole Moment
0.056 ± 0.004
Discovery Year1935
Parity+

20F Decay Modes
Decay ModeIntensity
β (β decay)100%

21F

AbundanceRadioactive ☢️
Relative Atomic Mass
20.999948893 ± 0.000001932 Da
Mass Number21
G-Factor
1.56776 ± 0.00048
Half Life
4.158 ± 0.02 s
Spin5/2
Quadrupole Moment
0.011 ± 0.002
Discovery Year1955
Parity+

21F Decay Modes
Decay ModeIntensity
β (β decay)100%

22F

AbundanceRadioactive ☢️
Relative Atomic Mass
22.002998812 ± 0.00001331 Da
Mass Number22
G-Factor
0.6736 ± 0.0001
Half Life
4.23 ± 0.04 s
Spin4
Quadrupole Moment
0.003 ± 0.002
Discovery Year1965
Parity+

22F Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)11%

23F

AbundanceRadioactive ☢️
Relative Atomic Mass
23.003526875 ± 0.00003577 Da
Mass Number23
G-Factor
Half Life
2.23 ± 0.14 s
Spin5/2
Quadrupole Moment
Discovery Year1970
Parity+

23F Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)14%

24F

AbundanceRadioactive ☢️
Relative Atomic Mass
24.00809937 ± 0.000104853 Da
Mass Number24
G-Factor
Half Life
384 ± 16 ms
Spin3
Quadrupole Moment
Discovery Year1970
Parity+

24F Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)5.9%

25F

AbundanceRadioactive ☢️
Relative Atomic Mass
25.012167727 ± 0.000103535 Da
Mass Number25
G-Factor
Half Life
80 ± 9 ms
Spin5/2
Quadrupole Moment
Discovery Year1970
Parity+

25F Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)23.1%
2n (2-neutron emission)%

26F

AbundanceRadioactive ☢️
Relative Atomic Mass
26.020048065 ± 0.000114898 Da
Mass Number26
G-Factor
Half Life
8.2 ± 0.9 ms
Spin1
Quadrupole Moment
Discovery Year1979
Parity+

26F Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)13.5%
2n (2-neutron emission)%

27F

AbundanceRadioactive ☢️
Relative Atomic Mass
27.026981897 ± 0.000129037 Da
Mass Number27
G-Factor
Half Life
5 ± 0.2 ms
Spin5/2
Quadrupole Moment
Discovery Year1981
Parity+

27F Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)77%
2n (2-neutron emission)%

28F

AbundanceRadioactive ☢️
Relative Atomic Mass
28.035860448 ± 0.000129198 Da
Mass Number28
G-Factor
Half Life
46 zs
Spin4
Quadrupole Moment
Discovery Year2012
Parity-

28F Decay Modes
Decay ModeIntensity
n (neutron emission)100%

29F

AbundanceRadioactive ☢️
Relative Atomic Mass
29.043103 ± 0.000564 Da
Mass Number29
G-Factor
Half Life
2.5 ± 0.3 ms
Spin5/2
Quadrupole Moment
Discovery Year1989
Parity+

29F Decay Modes
Decay ModeIntensity
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 Number30
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

30F Decay Modes
Decay ModeIntensity
n (neutron emission)%

31F

AbundanceRadioactive ☢️
Relative Atomic Mass
31.061023 ± 0.000574 Da
Mass Number31
G-Factor
Half Life
Spin5/2
Quadrupole Moment
Discovery Year1999
Parity+

31F Decay Modes
Decay ModeIntensity
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

DiscoverersHenri Moissan
Discovery LocationFrance
Discovery Year1886
Etymology (Name Origin)Latin: fluere (flow).
PronunciationFLU-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

1s0.3499
2p3.9
2s3.8724