Chemistry
Assertion (A): Hydrogen is placed in group I.
Reason (R): Hydrogen can gain an electron to achieve noble gas configuration.
- 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.
Periodic Table
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Answer
Both A and R are true but R is not the correct explanation of A.
Explanation — Hydrogen is placed in Group I with alkali metals because, like them, it has one electron in its outermost shell and forms (H⁺) ions by losing this electron. Although hydrogen can also gain an electron to form the hydride ion (H⁻) similar to halogens. Hence, Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
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