Chemistry
Assertion (A): Zinc is preferred for the laboratory preparation of hydrogen.
Reason (R): Zinc is unique in nature and does not contain any impurity.
- 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.
Hydrogen
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Answer
A is true but R is false.
Explanation — Zinc granules are preferred for laboratory preparation of hydrogen over pure zinc because the impurity present in granulated zinc is copper, whose catalysing effect speeds up the rate of reaction. Hence the assertion (A) is true.
Zinc is unique in nature and does contain impurity like copper. Hence reason (R) is false.
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