Chlorine Element

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  1. Chlorine Element Symbol
  2. Chlorine Element Sign
  3. Chlorine Element Charge
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History and Uses: Since it combines directly with nearly every element, chlorine is never found free in nature. Chlorine was first produced by Carl Wilhelm Scheele, a Swedish chemist, when he combined the mineral pyrolusite (MnO 2) with hydrochloric acid (HCl) in 1774. Chlorine is classified as a highly volatile element with a 50% T C of 472 K (Wood et al., 2019) (Table 1). Geochemically, it is a lithophile element. Geochemically, it is a lithophile element. On Earth, Cl is concentrated in Earth's surface reservoirs relative to the crust and mantle. Chlorine is the non-metallic chemical element of atomic number 17, symbol Cl, atomic weight 35.45, melting point -149.8°F (-101°C), and boiling point-29.02°F (-33.9°C). It consists of two stable isotopes, of mass numbers 35 and 37. Ordinary chlorine is a mixture of 75.77% chlorine-35 atoms and 24.23% chlorine-37 atoms.

Chlorine is a naturally-occurring chemical element, one of the basic building blocks of matter. Scattered throughout the rocks of Earth’s continents and concentrated in its salty oceans, chlorine is an essential nutrient for plants and animals. Chlorine chemistry provides clean drinking water to millions around the globe.

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Alternative Title: Cl

Chlorine (Cl), chemical element, the second lightest member of the halogen elements, or Group 17 (Group VIIa) of the periodic table. Chlorine is a toxic, corrosive, greenish yellow gas that is irritating to the eyes and to the respiratory system.

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Element Properties
atomic number17
atomic weight35.446 to 35.457
melting point−103 °C (−153 °F)
boiling point−34 °C (−29 °F)
density (1 atm, 0 °C or 32 °F)3.214 g/litre (0.429 ounce/gallon)
oxidation states−1, +1, +3, +5, +7
electron configuration1s22s22p63s23p5


Rock salt (common salt, or sodium chloride) has been known for several thousand years. It is the main constituent of the salts dissolved in seawater, from which it was obtained in ancient Egypt by evaporation. In Roman times, soldiers were partially paid in salt (salarium, the root of the modern word salary). In 1648 the German chemist Johann Rudolf Glauber obtained a strong acid, which he called spirit of salt, by heating moist salt in a charcoal furnace and condensing the fumes in a receiver. Later he obtained the same product, now known to be hydrochloric acid, by heating salt with sulfuric acid.

In 1774 the Swedish chemist Carl Wilhelm Scheele treated powdered black oxide of manganese with hydrochloric acid and obtained a greenish-yellowish gas, which he failed to recognize as an element. The true nature of the gas as an element was recognized in 1810 by English chemist Humphry Davy, who later named it chlorine (from the Greek chloros, meaning “yellowish green”) and provided an explanation for its bleaching action.

Occurrence and distribution

Apart from very small amounts of free chlorine (Cl) in volcanic gases, chlorine is usually found only in the form of chemical compounds. It constitutes 0.017 percent of Earth’s crust. Natural chlorine is a mixture of two stable isotopes: chlorine-35 (75.53 percent) and chlorine-37 (24.47 percent). The most common compound of chlorine is sodium chloride, which is found in nature as crystalline rocksalt, often discoloured by impurities. Sodium chloride is also present in seawater, which has an average concentration of about 2 percent of that salt. Certain landlocked seas, such as the Caspian Sea, the Dead Sea, and the Great Salt Lake of Utah, contain up to 33 percent dissolved salt. Small quantities of sodium chloride are present in blood and in milk. Other chlorine-containing minerals are sylvite (potassium chloride [KCl]), bischofite (MgCl2 ∙6H2O), carnallite (KCl∙MgCl2 ∙6H2O), and kainite (KCl∙MgSO4 ∙3H2O). It is found in evaporite minerals such as chlorapatite and sodalite. Free hydrochloric acid is present in the stomach.

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Chlorine Element Symbol

Present-day salt deposits must have been formed by evaporation of prehistoric seas, the salts with the least solubility in water crystallizing first, followed by those with greater solubility. Because potassium chloride is more soluble in water than sodium chloride, certain rock salt deposits—such as those at Stassfurt, Germany—were covered by a layer of potassium chloride. In order to gain access to the sodium chloride, the potassium salt, important as a fertilizer, is removed first.

Chlorine Element Sign

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Chlorine Element Charge

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