Question

Study the following table in which positions of six elements A,B,C, D, E and F are shown as they are in the modern periodic table :

Group→ Period↓	1	2	3-12	13	14	15	15	17	18
1. 2.	A			D	E	B			C F

On the basis of the above table,answer the following questions:

(i) Name the element which forms only covalent compounds.

(ii) Name the element which is a metal with valency three.

(iii) Name the element which is a non-metal with valency three.

(iv) Out of D and E, which is bigger is size and why ?

(v) Write the common name for the family to which the elements C and F belong.

Answer 1

(i) Element E will form covalent compounds by sharing its four valence electrons. 

(ii) Element D is a metal with valency three. 

(iii) Element B is a non-metal with valency three. 

(iv) We know that the size of elements decreases on moving left to right in a period. Therefore, element D is greater than element E. 

(v) The name of the family to which elements C and F belong is the noble gas family (group 18).