Question

Which of the following element has the smallest size in its group?

(a) sodium

(b) rubidium

(c) potassium

(d) lithium

I have been asked this question in an international level competition.

I'd like to ask this question from s-Block Elements in portion s-Block Elements of Chemistry – Class 11

Answer 1

Right answer is (d) lithium

To explain: The element Lithium whose atomic number is given by 3 is the smallest element in its group that is alkali metals by size. This is one of the reasons why it has anomalous behavior in the periodic table comparatively.