Chlorine

Atomic symbol: Cl
Atomic number: 17
Atomic mass: 35.45

Appearance: yellow-green gas at 25°C

Group: 17
Period: 3
Series: Halogens (reactive nonmetals)
Block: p
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁵

Extremly reactive and a strong oxidising agent. Chlorine has the highest electron affinity and the third-highest electronegativity.

Most common compound is sodium chloride, table salt.

Fun Fact! While elemental chlorine is poisonous to most living organisms, chloride compounds are essential to life. In the human body, chlorides are used for digestion, muscle contraction, and much more.

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