Atomic number:9

Group numbers:17

Period:2

Electronic configuration:[He] 2s² 2p⁵

Formal oxidation number:-1

Electronegativities:3.98

Atomic radius / pm:70.9

Relative atomic mass:18.9984032 ± 0.0000005

 

Fluorine was discovered by Henri Moissan (FR) in 1886. The origin of the name comes from the Latin word fluere meaning to flow. It is a pale yellow to greenish gas, with an irritating pungent odour. Fluorine is a extremely reactive, flammable gas. It reacts violently with many materials. It is toxic by inhalation or ingestion. Fluorine doesn't occur elementary in nature. Fluorine is found in minerals: fluorite (CaF2) and cryolite (Na3AlF6). Electrolysis of hydrofluoric acid (HF) or potassium acid fluoride (KHF2) is the only practical method of commercial production. It is used in refrigerants, other fluorocarbons and in toothpaste as sodium fluoride (NaF).

Density / g dm^-3:1516 (liquid, 85 K)

 1.696 (gas, 273 K)

Molar volume / cm³mol^-1:12.53 (liquid, 85 K)

 22403.78 (gas, 273 K)

Electrical resistivity / μΩcm:- (20 °C)

Thermal conductivity / W m^-1K^-1:0.0256

Melting point / °C:-219.62

Boiling point / °C:-188.12

Heat of fusion / kJ mol^-1:1.02

Heat of vaporization / kJ mol^-1:3.26

Heat of atomization / kJ mol^-1:76.9

1st ionization energy / kJ mol^-1:1681.06

2nd ionization energy / kJ mol^-1:3374.20

3rd ionization energy / kJ mol^-1:6050.48

in the atmosphere / ppm:-

in the Earth's crust / ppm:625

in the oceans / ppm:1.3