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प्रश्न
What do you mean by a precipitation reaction? Explain giving an example.
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उत्तर १
When two solutions containing soluble salts are combined, a double-displacement reaction occurs in which ions are exchanged between the compounds. When one such compound is in solid form (that is, insoluble in water), it settles to the bottom of the container. This solid is known as the precipitate, and the respective reaction is termed the precipitation reaction. A few examples of precipitation reactions are:
- \[\ce{CdSO4_{(aq)} + K2S_{(aq)} -> CdS_{(s)} + K2SO4_{(aq)}}\]
- \[\ce{2NaOH_{(aq)} + MgCl2_{(aq)} -> 2NaCl_{(aq)} + Mg(OH)2_{(s)}}\]
उत्तर २
Any reaction in which an insoluble solid (called a precipitate) is formed that separates from the solution is called a precipitation reaction.
If barium chloride solution is added to copper sulphate solution, then a white precipitate of barium sulphate is produced along with copper chloride solution:
\[\ce{\underset{Barium chloride}{BaCl2_{(aq)}} + \underset{Copper sulphate}{CuSO4_{(aq)}} -> \underset{(White ppt{.})}{\underset{Barium sulphate}{BaSO4_{(s)}}} + \underset{Copper chloride}{CuCl2_{(aq)}}}\]
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संबंधित प्रश्न
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What type of chemical reaction is represented by the following equation?
\[\ce{PQ + RS -> PS + RQ}\]
What type of reaction is represented by the following equation?
\[\ce{CuSO4 + 2NaOH -> Cu(OH)2 + Na2SO4}\]
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Name the type of reaction involved.
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- What is metal X?
- What is salt XNO3?
- Name the compound Y.
- Write the chemical equation of the reaction which takes place on reacting XNO3 solution and common salt solution giving the physical states of all the reactants and products.
- What type of chemical reaction is illustrated by the above equation?
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- What could the salt XSO4 be?
- What is the colour of salt XSO4?
- Name the black precipitate XS.
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- What type of chemical reaction takes place in this case?
Give scientific reason.
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In a double displacement reaction such as the reaction between sodium sulphate solution and barium chloride solution:
- exchange of atoms takes place
- exchange of ions takes place
- a precipitate is produced
- an insoluble salt is produced
The correct option is:
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The following reaction is an example of:
\[\ce{4NH3_{(g)} + 5O2_{(g)} -> 4NO_{(g)} + 6H2O_{(g)}}\]
(i) displacement reaction
(ii) combination reaction
(iii) redox reaction
(iv) neutralisation reaction
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`"TiCl"_4("l") + "Mg"("s") -> "Ti"("s") + "MgCl"_2("s")`
In a double displacement reaction ______.
A chemical reaction in which exchange of ions occurs between the reactants is known as ______.
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Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
