SSC
CHEMISTRY
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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sediment
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fractional crystallization
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element
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precipitate
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Detailed explanation-1: -Precipitation is the process of formation of an insoluble solid when solutions are mixed. The solid thus formed is called precipitate. Only those compounds form precipitates which are insoluble in water.
Detailed explanation-2: -Substances with relatively large solubilities are said to be soluble. A substance will precipitate when solution conditions are such that its concentration exceeds its solubility. Substances with relatively low solubilities are said to be insoluble, and these are the substances that readily precipitate from solution.
Detailed explanation-3: -Precipitation reactions occur when cations and anions in aqueous solution combine to form an insoluble ionic solid called a precipitate.
Detailed explanation-4: -Compounds having anions such as sulfide (S2−), hydroxide (OH−), carbonate (CO32−), and phosphate (PO43−) are often insoluble in water. A precipitate will form if a solution containing one of these anions is added to a solution containing a metal cation such as Fe2+, Cu2+, or Al3+.