The elements of the second period along with their atomic numbers in parentheses are given below: B (5), Be (4), O (8), N (7), Li (3), C (6), F (9) (i) Arrange them in the same order as they appear in the periodic table. (ii) Which element has the largest and smallest atom?
(a) (i) Li (3), Be (4), B (5), C (6), N (7), O (8), F (9) (ii) The element Li has the largest atom. The element F has the smallest atom. (b) Along a period, the nuclear charge increases and the electrons are attracted more towards the nucleus. Therefore, the atomic size or atomic radius decreases as we move from left to the right along a period.
