Assertion: Alkali metals are highly reactive.
Reason: Alkali metals have only one valence electron that is easily removed, making them highly reactive with other elements.
(a) Both Assertion (A) and Reason (R) are the true and Reason (R) is a correct explanation of Assertion (A).
Both Assertion (A) and Reason (R) are the true but Reason (R) is not a correct explanation of Assertion (A).
Assertion (A) is true and Reason (R) is false.
Assertion (A) is false and Reason (R) is true.
The assertion is true because alkali metals have only one valence electron, which is easily removed. This makes them highly reactive with other elements because they can easily form cations, which are positively charged ions. Alkali metals react vigorously with water, acids, and halogens, which are examples of their high reactivity.