Chemistry
Assertion (A): Though hydrogen is lighter than air, it is not collected by the downward displacement of air but by the downward displacement of water.
Reason (R): Hydrogen is slightly soluble in water.
- 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 — Hydrogen is collected by the downward displacement of water because it forms an explosive mixture with air and therefore cannot be collected by downward displacement of air even though it is lighter than air. Hence the assertion (A) is true.
Hydrogen is virtually insoluble in water (does not dissolve in water). Hence the reason (R) is false.
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