Science
When 50 g of lead powder is added to 300 ml of blue copper sulphate solution, after a few hours, the solution becomes colourless. This is an example of
options
- Combination reaction
- Decomposition reaction
- Displacement reaction
- Double displacement reaction
Answer
Displacement reaction
Reason — When lead (Pb) powder is added to copper sulphate (CuSO4) solution, a chemical reaction takes place in which lead displaces copper from its compound because lead is more reactive than copper.
The blue colour of the CuSO4 solution gradually fades and finally becomes colourless, as lead sulphate (PbSO4), which is white, is formed, and reddish-brown copper (Cu) metal gets deposited.
The reaction is:
Pb(s) + CuSO4(aq) ⟶ PbSO4(s) + Cu(s)
This is an example of a single displacement reaction, where a more reactive metal (Pb) displaces a less reactive metal (Cu) from its salt solution.
Related Questions
Which among the following is considered as the strongest electrolyte?
options
- Dilute acid
- Dilute sugar solution
- Glucose solution
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An aqueous solution ‘A’ turns the phenolphthalein solution pink. On addition of an aqueous solution ‘B’ to ‘A’, the pink colour disappears. Which of the following statement is true for the solutions ‘A’ and ‘B’.
options
- A is strongly basic and B is a weak base.
- A is strongly acidic and B is a weak acid.
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options
- Y and Z are metals
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Which of the following is an endothermic reaction?
options
- Burning of candle.
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- Decomposition of Vegetable matter.
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