Science
Assertion (A) : The colour of aqueous solution of copper sulphate turns colourless when a piece of lead is added to it.
Reason (R) : Lead is more reactive than copper, and hence displaces copper from its salt solution.
- Both (A) and (R) are true and (R) is the correct explanation of (A).
- Both (A) and (R) are true, but (R) is not the correct explanation of (A).
- (A) is true, but (R) is false.
- (A) is false, but (R) is true.
Answer
Both (A) and (R) are true and (R) is the correct explanation of (A)
Reason — When a piece of lead is added to an aqueous solution of copper sulphate, a displacement reaction takes place as lead is more reactive than copper hence lead displaces copper from the copper sulphate solution. The chemical equation for the reaction is:
Pb + CuSO4 ⟶ PbSO4 + Cu
This results in a colorless solution [PbSO4].
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Reason (R) : X chromosome in a male child is inherited from his father.
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Reason (R) : Blood clotting is due to blood plasma and white blood cells present in the blood.
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