9F18.998
Fluorine
Halogen · element 9 · group 17, period 2
Quick facts
| Symbol | F |
|---|---|
| Atomic number | 9 |
| Relative atomic mass | 18.998 |
| Category | Halogen |
| Position | group 17, period 2 |
| State at 20 °C | Gas |
| Melting point | -219.7 °C |
| Boiling point | -188.1 °C |
| Density | 0.002 g/cm³ |
| Electronegativity | 3.98 |
| Electron configuration | [He] 2s2 2p5 |
About Fluorine
Fluorine has the symbol F and atomic number 9, which means every fluorine atom has 9 protons in its nucleus and, in a neutral atom, 9 electrons. At room temperature it is a gas.
Halogens are in group 7. They have 7 outer electrons, exist as diatomic molecules (like Cl₂), and get less reactive going down the group.
It melts at -219.7 °C and boils at -188.1 °C.
Explore it
See where fluorine sits, and drag the temperature slider to watch it melt and boil, on the interactive periodic table. Practise with quizzes on OmniEx.