17Cl
Element 17
Chlorine
Halogens
Chlorine is a chemical element with symbol Cl and atomic number 17.
Key data
- Atomic number
- 17
- Atomic mass
- 35.450 u
- Group / Period
- 17 / 3
- Block
- p-block
- Phase at STP
- Gas
- Density
- 3.2 g/cm³
- Melting point
- -101.5 °C
- Boiling point
- -34.0 °C
- Electron configuration
- [Ne] 3s2 3p5
Common uses
- •Pool sanitizer
- •Bleach
- •PVC plastics
Discovery
Year: 1774
Discovered by: Carl Wilhelm Scheele
Frequently asked questions
What is the atomic number of Chlorine?
Chlorine has atomic number 17. Its symbol is Cl and its atomic mass is 35.45 u.
What category of element is Chlorine?
Chlorine is classified as halogens. It sits in group 17, period 3 of the periodic table.
What is Chlorine used for?
Common uses of Chlorine include: Pool sanitizer, Bleach, PVC plastics.
When was Chlorine discovered?
Chlorine was discovered in 1774 by Carl Wilhelm Scheele.
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