Chemistry
Assertion (A): Hydrogen can be placed in two groups i.e., with Alkali metals and with halogens.
Reason (R): Hydrogen has two electrons in its valence shell.
- 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
A is true but R is false.
Explanation — Hydrogen resembles the alkali metals of Group IA and the halogens of Group VIIA. This is due to the fact that it has only one electron in its valence shell, hence it behaves like the alkali metals which have one valence electron. At the same, it also behaves like halogens as it has just one electron less than the nearest inert gas. Hence the assertion (A) is true.
Hydrogen has only one electron in its valence shell. Hence reason (R) is false.
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