(a) Explain why the first period of the modern periodic table has only two elements whereas second period has eight elements
(b) Why do elements in the same group show similar properties but the elements in different groups show different properties?
(c) For each of the following triads, name the element with the characteristics specified below:

(d) State on reason for keeping fluorine and chlorine in the same group of the periodic table.
(e) What are the merits of the moderns periodic table of elements?

Answer

(c) (i) `F;Br` (ii) `Li, Li`

Explanation

NA