Chlorine (Cl) — Halogen. Atomic number 17.
Greenish-yellow gas
- Atomic number: 17
- Symbol: Cl
- Atomic mass: 35.45 u
- Category: Halogen
- State: Gas
- Melting point: -101.55 °C / 171.6 K
- Boiling point: -34.05 °C / 239.1 K
- Density: 3.21e-3 g/cm³ (20°C)
- Electron configuration: [Ne] 3s2 3p5
- Oxidation states: −1, +1, +3, +5, +7
- Electronegativity: 3.16
- Discovered by: Carl Wilhelm Scheele (1774)
Common uses: Water treatment, PVC production, Bleaching agents
Biological role: Essential electrolyte in body fluids.
Frequently Asked Questions about Chlorine
What is the atomic number of chlorine?
Chlorine has an atomic number of 17, meaning each atom contains 17 protons in its nucleus.
What is the atomic mass of chlorine?
The standard atomic weight of chlorine is 35.45 u (unified atomic mass units).
What category does chlorine belong to?
Chlorine is classified as a halogen.
What is the state of chlorine at room temperature?
Chlorine is a gas at 20 °C (68 °F).
What is the melting point of chlorine?
The melting point of chlorine is -101.55 °C / 171.6 K.
What is the boiling point of chlorine?
The boiling point of chlorine is -34.05 °C / 239.1 K.
What is the density of chlorine?
The density of chlorine is 3.21e-3 g/cm³ (20°C).
What is the electronegativity of chlorine?
Chlorine has a Pauling electronegativity of 3.16.
What is the electron configuration of chlorine?
The electron configuration of chlorine is [Ne] 3s2 3p5.
What are the common oxidation states of chlorine?
Chlorine commonly exhibits the following oxidation states: −1, +1, +3, +5, +7.
When was chlorine discovered?
Chlorine was discovered in 1774 by Carl Wilhelm Scheele.
Is chlorine radioactive?
Chlorine is a stable element with no naturally occurring radioactive isotopes.
What is the biological role of chlorine?
Essential electrolyte in body fluids.
What are the common uses of chlorine?
Chlorine is used for: Water treatment; PVC production; Bleaching agents.
