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Chlorine Element in Periodic Table | Atomic Number Atomic Mass


Chlorine Element:

Chlorine is the second element in the seventeenth group of the periodic table. Its atomic number is 17 and represented by the symbol Cl. After oxygen and fluorine it has the highest electron affinity and third-highest electronegativity. At room temperature Chlorine is a yellow-green gas. Chlorine gas has a very strong odor and is poisonous to humans. Cl is too reactive to occur as the free element in nature, but it is found only in compounds with other elements. Sodium chloride is the most common compound of chlorine. Cl is the twenty-first most abundant chemical element in Earth's crust. It  has 24 isotopes; among them two are stable, 35Cl and 37Cl.

Uses Of Chlorine Element:

  • Chlorine is used in making drinking water safe and to treat swimming pools because it kills bacteria.
  • is also used in making the products such as insecticides, pharmaceuticals, cleaning products, textiles, and plastics.
  • Cl is used for bleaching purposes.
  • It is used as an oxidising agent and in substitution reactions. Cl is used as a necessary ingredient in manufacture of medicinal drugs by about 85% of pharmaceuticals.


Chlorine Element Information:

Discovery year: 1774

Discovered by: Carl Wilhelm Scheele

Atomic number:17

Relative atomic mass:35.45 

Electron configuration: [Ne] 3s2 3p5

Block: p-block

Other elements in the same block:

Boron, Carbon, Nitrogen, Oxygen, Fluorine, Neon, Aluminum, Silicon, Phosphorus, Sulfur, Argon, Gallium, Germanium, Arsenic, Selenium, Bromine, Krypton, Indium, Tin, Antimony, Tellurium, Iodine, Xenon, Thallium, Lead, Bismuth, Polonium, Astatine, Radon, Nihonium, Flerovium, Moscovium, Livermorium, Tennessine and Oganesson are the same block elements.

Period: period 3

Other elements in the same period:

Sodium, Magnesium, Aluminium, Silicon, Phosphorus, Sulfur and Argon

Group: group 17 (halogens)

Other elements in the same group:

Fluorine, Bromine, Iodine, Astatine and Tennessine are the same group elements.

Other elements in the same orbital:

Aluminium, Silicon, Phosphorus, Sulfur and Argon are the elements in the same orbital.

Allotropes:  none

Key isotopes: 35Cl, 37Cl 

Melting point: −101.5°C, −150.7°F, 171.7 K

Boiling point: −34.04°C, −29.27°F, 239.11 K

Element category: diatomic non-metal

Density (g cm−3): 0.002898

CAS number: 7782-50-5

Color: pale yellow-green gas

You can know detailed information for each element,

Hydrogen, HeliumLithiumBerylliumBoronCarbonNitrogenOxygenFluorine,  Neon , SodiumMagnesiumAluminiumSiliconPhosphorusSulfurChlorineArgon, PotassiumCalciumScandiumTitaniumVanadiumChromiumManganeseIronCobaltNickelCopperZincGalliumGermaniumArsenicSeleniumBromine, Krypton,  Rubidium, StrontiumYttriumZirconiumNiobiumMolybdenumTechnetiumRutheniumRhodiumPalladiumSilverCadmiumIndiumTinAntimonyTelluriumIodine, Xenon,  Caesium, BariumLanthanum,  CeriumPraseodymiumNeodymiumPromethiumSamariumEuropiumGadoliniumTerbiumDysprosiumHolmiumErbiumThuliumYtterbiumLutetiumHafniumTantalumTungstenRheniumOsmiumIridiumPlatinumGoldMercuryThalliumLeadBismuthPoloniumAstatine, Radon,  Francium, RadiumActiniumThoriumProtactiniumUraniumNeptuniumPlutoniumAmericiumCuriumBerkeliumCaliforniumEinsteiniumFermiumMendeleviumNobeliumLawrenciumRutherfordiumDubniumSeaborgiumBohriumHassiumMeitneriumDarmstadtiumRoentgeniumCoperniciumNihoniumFleroviumMoscoviumLivermoriumTennessine, Oganesson.

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