Question

The elements of the second period of the Periodic Table are given below: Li Be B C N O F
(a) Atomic radii decrease from Li to F. Give reason.
(b) Identify the most metallic and non-metallic element.

Answer 1

(a) It is because nuclear charge increases due to an increase in atomic number, therefore, the force of attraction between the nucleus and valence electrons increases, i.e. effective nuclear charge increases, hence atomic radii decrease from Li to F.
(b) Most metallic element is ‘Li’ as it can lose electrons easily due to larger atomic size and the most non-metallic element is ‘F’ because it can gain electrons easily due to its smallest atomic size.