SSC
CHEMISTRY
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which substance is an element?
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Water (H2O)
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Ammonia (NH3)
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Chlorine (Cl)
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Carbon Dioxide (CO2)
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Explanation:
Detailed explanation-1: -Chlorine is a chemical element with the symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature.
Detailed explanation-2: -Chlorine is pronounced as KLOR-een or as KLOR-in. 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 (MnO2) with hydrochloric acid (HCl) in 1774.
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