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प्रश्न
What is meant by a displacement reaction? Explain with the help of one example.
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उत्तर
Those reactions in which one element replaces another in a compound are known as displacement reactions. In general, a more reactive element displaces a less reactive element from its compound.
When a strip of zinc metal is placed in a copper sulphate solution, zinc sulphate solution and copper are formed.
\[\ce{\underset{(Blue solution)}{\underset{Copper sulphate}{CuSO4_{(aq)}}} + \underset{(Silvery white)}{\underset{Zinc}{Zn_{(s)}}} -> \underset{(Colourless solution)}{\underset{Zinc sulphate}{ZnSO4_{(aq)}}} + \underset{(Red-brown)}{\underset{Copper}{Cu_{(s)}}}}\]
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संबंधित प्रश्न
Reaction of iron nails with copper sulphate solution is an example of
(a) Combination reaction
(b) Decomposition reaction
(c) Displacement reaction
(d) Double displacement reaction
CuSO4(aq) + Zn(s) → ZnSO4(aq) + Cu(s) is an example of a decomposition reaction.
In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involved.
What type of chemical reaction is represented by the following equation?
\[\ce{A + BC -> AC + B}\]
Which of the following is a combination and which is a displacement reaction?
- \[\ce{Cl2 + 2KI -> 2KCl + I2}\]
- \[\ce{2K + Cl2 -> 2KCl}\]
A strip of metal X is dipped in a blue coloured salt solution YSO4. After some time, a layer of metal Y from the salt solution is formed on the surface of metal strip X. Metal X is used in galvanisation whereas metal Y is used in making electric wires. Metal X and metal Y together form an alloy Z.
- What could metal X be?
- What could metal Y be?
- Name the metal salt YSO4.
- What type of chemical reaction takes place when metal X reacts with salt solution YSO4? Write the equation of the chemical reaction involved.
- Name the alloy Z.
The colour of an aqueous solution of zinc sulphate as observed in the laboratory is:
(1) Green
(2) Yellow
(3) Blue
(4) Colourless
To show that zinc is a more active metal than copper, the correct procedure is to:
(1) add dilute nitric acid on strips of both the metals.
(2) observe transmission of heat through strips of zinc and copper.
(3) prepare solution of zinc sulphate and hang strip of copper into it.
(4) prepare solution of copper sulphate and hang strip of zinc into it.
Explain the terms with examples.
Displacement reaction
i) Observe the following reaction and answer the following questions.
`CuSO_4 (aq) + Fe (s) → FeSO_4(aq) + Cu (s)`
a) Identify and write the type of chemical reaction.
b) Write the definition of above reaction.
Identify the type of reaction taking place in the following case and write the balanced chemical equation for the reaction.
Zinc reacts with silver nitrate to produce zinc nitrate and silver.
Classify the following reaction into different type:
AgNO3(aq) + NaCl(aq) →AgCl(s) + NaNO3(aq)
Classify the following reaction into different type:
Zn + CuSO4 → ZnSO4 + Cu
Give reasons for the following:
The reaction of iron (III) oxide [Fe2O3] with heated aluminum is used to join cracked machine parts.
Give a balanced equation for –
A displacement reaction involving a metal above hydrogen in the activity series with copper [II] sulphate solution
Match the following
Identify the types of reactions.
| REACTION | TYPE |
| NH4OH(aq) + CH3COOH(aq) → CH3COONH4(aq) + H2O(l) | Single Displacement |
| Zn(s) + CuSO4(aq) → ZnSO4(aq) + Cu(s) | Combustion |
| \[\ce{ZnCO3_{(s)} + ->[Heat]ZnO_{(s)} + CO2_{(g)}}\] | Neutralization |
| C2H4(g) + 4O2(g) → 2CO2(g) + 2H2 O(g) + Heat | Thermal decomposition |
The colour of the solution observed after 30 minutes of placing zinc metal in copper sulphate solution is ______.
