Precipitation Reaction

Q.

What is double displacement reaction. Give an example.

Q.

Question 43

On adding a drop of barium chloride solution to an aqueous solution of sodium sulphite, white precipitate is obtained.

(a) Write a balanced chemical equation of the reaction involved.

(b) What other name can be given to this precipitation reaction?

(c) On adding dilute hydrochloric acid to the reaction mixture, white precipitate disappears. Why?

Q.

In the refining of silver, the recovery of Silver from Silver nitrate solution involves displacement reaction by Copper metal. Write down the reaction involved.

Q.

What happens when zinc reacts with copper sulphate solution?

Q.

A white precipitate can be obtained by adding dilute sulphuric acid to :

(a) $CuS{O}_4$ Solution (b) NaCI Solution (c) $BaC{I}_4$ Solution (d) $N{a}_{2}S{O}_4$ Solution

Q.

A white precipitate will be formed if we add common salt solution to :

(a) $Ba(N{O}_3{)}_2$ solution (b) $KN{O}_3$ solution (c) $AgN{O}_3$ solution (d) $Mg(N{O}_3{)}_2$ solution

Q.

$BaC{l}_2\left(aq\right)+N{a}_{2}S{O}_4\left(aq\right)\to BaS{O}_4\left(ppt\right)+2NaCl\left(aq\right)$

What is the colour of precipitate formed?

1. White

2. Black

3. Yellow

4. Blue

Q. Assertion: A lead nitrate on thermal decomposition gives lead oxide, brown coloured nitrogen dioxide and oxygen gas.
Reason: Lead nitrate reacts with potassium iodide to form yellow ppt of lead iodide and the reaction is double displacement as well as precipitation reaction.

1. Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion
2. The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion
3. Assertion is true but the Reason is false
4. The statement of the Assertion is false but the Reason is true

Q.

Which metallic container is suitable to store copper sulfate solution?

Q.

How are the following indicated in a chemical equation?

formation of precipitate

Q.

NaCl + AgNO₃ → AgCl + NaNO₃ is an example of:

1. Double displacement reaction

2. Combustion reaction

3. Combination reaction

4. Decomposition reaction

Q.

Which of the following is not a decomposition reaction?

1. CaCO₃ → CaO + CO₂

2. 2KClO₃ →2KCl + 3O₂

3. Digestion of food in the body.

4. H₂ + Cl₂ → 2HCl

Q. Question 15

What do you mean by a precipitation reaction? Explain by giving examples.

Q. A double displacement reaction is always characterised by the formation of a precipitate.

1. True
2. False

Q. Identify the type of reaction in the following.

$\left(a\right){\mathrm{ZnCO}}_{3\left(aq\right)}+2\mathrm{HCl}\left(\mathrm{aq}\right)\to {\mathrm{ZnCl}}_2\left(\mathrm{aq}\right)+H_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)\left(b\right)2\mathrm{NaBr}\left(\mathrm{aq}\right)+{\mathrm{Cl}}_2\left(g\right)\to 2\mathrm{Na}Cl\left(\mathrm{aq}\right)+{\mathrm{Br}}_2\left(\mathrm{aq}\right)\left(c\right)2\mathrm{CuO}\left(s\right)\stackrel{\mathrm{Heat}}{\to }2\mathrm{Cu}\left(s\right)+O_2\left(g\right)$

Q. All of the following reactions result in the formation of a white coloured precipitate in the solution, except

1. reaction of barium chloride and sodium sulphate
2. reaction of sodium chloride and silver nitrate
3. reaction of lime water and carbon dioxide
4. reaction of potassium iodide and lead nitrate

Q.

The addition of oxygen to a substance is called reduction

1. True
2. False

Q. When hydrogen sulphide gas is passed through a blue solution of copper sulphate, a black precipitate of copper sulphide is obtained and the sulphuric acid so formed remains in the solution. The reaction is an example of:

1. A combination reaction
2. A displacement reaction
3. A decomposition reaction
4. A double displacement reaction

Q. A displacement reaction is always characterised by the formation of a precipitate.

1. True
2. False

Q.

Which of the following statements is correct?

1. Only one reactant is involved in a combination reaction

2. Only one product is formed in a decomposition reaction

3. Electrolytic decomposition reactions require electricity

4. Photolytic decomposition reactions require heat

Q.

__ is the process of formation of an insoluble solid when solutions are mixed.

Q. What is Metathesis reactions?

Q.

On combining two aqueous solutions of soluble ionic compounds, a precipitate is formed when

1. the reactant is insoluble.

2. the product is insoluble.

3. the solvent is insoluble.

4. a gas is evolved.

Q.

What is decomposition reaction?

Q. What will be the colour of the precipitate formed when ferrous sulphate is added to an aqueous solution of sodium hydroxide?

[1 mark]

1. Dirty green
2. Reddish brown
3. Pale blue
4. White

Q.

What is precipitate?Please answer with a easy example of precipitate in a chemical reaction.

Q. Sodium hydroxide solution is added to the solutions containing the ions mentioned in List X. List Y gives the details of the precipitate. Match the ions with their coloured precipitates.

List X	List Y
(i) Pb2+	(A) Reddish brown
(ii) Fe2+	(B) White insoluble in excess
(iii) Zn2+	(C) Dirty green
(iv) Fe3+	(D) White soluble in excess
(v) Cu2+	(E) White soluble in excess
(vi) Ca2+	(F) Blue

Q.

The reactions in which precipitate is formed are known as:

1. Precipitation reactions

2. Exothermic reactions

3. Combustion reactions

4. Endothermic reactions

Q. Using ammonium hydroxide, how would you distinguish between the following pairs of ions in solution:
(a) Ferrous ion and Ferric ion.
(b) Zinc ion and Lead ion.

Q. How will we come to know which colour precipitate is formed in the double displacement reaction?