Fluorine

Chaitra 26/06/2026 19:58:08 Updated 26/06/2026 19:58:08

Property	Value
Atomic Number	9
Element	Fluorine
Symbol	F
Atomic Mass	18.998 u
Number of Neutrons	10 (most common isotope, Fluorine-19)
Number of Protons	9
Number of Electrons	9
Period	2
Group	17
Phase	Gas
Radioactive	No
Natural	Yes
Metal	No
Nonmetal	Yes
Metalloid	No
Type	Halogen
Atomic Radius	42 pm
Electronegativity	3.98 (Pauling scale)
First Ionization Energy	17.423 eV
Density	0.001696 g/cm³
Melting Point	−219.67 °C
Boiling Point	−188.11 °C
Number of Isotopes	1 (Fluorine-19)
Discoverer	Henri Moissan
Year	1886
Specific Heat	0.824 J/g·K
Number of Shells	2
Number of Valence Electrons	7