QQuestion
Given below are a few elements.
Li, Li, K, Ca, F
Identify the element which:
(a) has the least atomic radius.
(b) has two valence electrons.
(c) is the most electropositive.
Exam-ready answer • 03 Mark
✓Answer
(a) Fluorine (F)
(b) Calcium (Ca)
(c) Potassium (K)
Explanation –
(a) Fluorine (F) has the least atomic radius. It is on the rightmost side of period 2, where atomic radius is minimum.
(b) Calcium (Ca) has two valence electrons (electronic configuration: 2, 8, 8, 2). It belongs to Group 2 of the periodic table.
(c) Potassium (K) is the most electropositive. Within Group 1, electropositive character increases down the group; potassium is below lithium and hence is more electropositive.
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