Question

Two elements 'A' and 'B' belong to the 3rd period of Modern periodic table and are in group 2 and 13 respectively. Compare their following characteristics in tabular form : 

(i) Number of electrons in their atoms 

(ii) Size of their atoms 

(iii) Their tendencies to lose electrons

(iv) The formula of their oxides

(v) Their metallic character

(vi) The formula of their chlorides.

Answer 1

Sr. No.	Characteristics	A	B
(i)	Number of electrons in their atoms	4 or 12or 20	5 or13 or 21
(ii)	Size of their atoms	Bigger	Smaller
(iii)	Their tendencies to lose electrons	More	Less
(iv)	The formula of their oxides	AO	B2O3
(v)	Their metallic character	More metallic	Less metallic
(vi)	The formula of their chlorides	ACl2	BCl3

Comments

How no. Of electrons in A is 4or 12 or 20 and in B is 5 or 13 or 21?