Question

what is the periodic trend in the variation of valency while going down a group explain your answer with reference the group 1 group 2 and group 18

Answer 1

THERE IS NO CHANGE IN THE VALENCE ELECTRONS WHILE MOVING DOWN A GROUP,BUT NUMBER OF SHE'LL INCREASES In group 1 ,
The valence electron is one,so the number of valence electron which is one will be same for all elements.
In group 2 ,
The valence electron is two, so the number of valence electron which is one will be same for all elements.
In group 18,
The elements neither gains or loses electrons because they are stable.

Answer 2

Answer:

(i) All the elements in a group have the same number

of electrons in the outermost shell. Therefore,

down the group, valency remains the same.

(ii) Valency of group 1 elements is 1 and that of group

2 elements is 2.

(iii) The valency of group 18 elements is zero because

they are noble gases with completed outermost

shell.

Explanation: