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Question
What do you mean by a precipitation reaction? Explain by giving examples.
Solution
When two solutions containing soluble salts are combined, a double displacement reaction takes place in which the ions are exchanged between the compounds. When one such compound is in solid form (that is insoluble in aqua), then it settles down at the bottom of the container. This solid is known as the precipitate and the respective reaction is termed as the precipitation reaction. A few examples of precipitation reactions are:
- \[\ce{CdSO4(aq) + K2S(aq) -> CdS(s) + K2SO4(aq)}\]
- \[\ce{2NaOH(aq) + MgCl2(aq) -> 2NaCl(aq) + Mg(OH)2(s)}\]
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RELATED QUESTIONS
Give an example of a double displacement reaction other than the one given in the following Activity.
•Take about 3 mL of sodium sulphate
solution in a test tube.
• In another test tube, take about 3 mL of
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• What do you observe?
Write the balanced chemical equation for the following and identify the type of reaction.
\[\ce{Potassium bromide (aq) + Barium iodide (aq) -> Potassium iodide (aq) + Barium bromide (s)}\]
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PQ + RS → PS + RQ
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Name the type of reaction involved.
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Potassium iodide reacts with lead nitrate to produce potassium nitrate and lead iodide.
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Write balanced chemical equation for the following word equation.
Lead nitrate + Potassium iodide → Lead iodide + Potassium nitrate
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