Assertion (A): The tendency of losing electrons increases down the Group.
Reason (R): The most reactive metal is placed at the top of Group 1.
(a) Both (A) and (R) are true, and (R) is the correct explanation of (A).
(b) Both (A) and (R) are true, and (R) is not the correct explanation of (A).
(c) (A) is true but (R) is false.
(d) (A) is false but (R) is true.
(c) (A) is true but (R) is false.
Explanation:
As we move down any group in the periodic table, atomic size increases and the outermost electron is held less tightly by the nucleus. Therefore the loss of this electron becomes easier, so the tendency to lose electrons increases; Assertion (A) is true. In group 1 the reactivity of metals increases down the group for the same reason. Consequently, the most reactive metal is found at the bottom, not at the top; Reason (R) is false.
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