Question

1.
State how do the following change in a period from left to right?
(a) Number of shells
(b) Valence electrons.
(c) Valency..
(d) Size of atoms ........
(e) Metallic character....
(f) Nature of oxides​

Answer 1

Answer:

on moving from left to right number of shells remain the same

the number of valence electrons in the valence shell increases from left to right

valency increases from left to right but only upto group 14 where it becomes 4 and then it decreases that means it becomes 1 in group 17

the size of atom decreases from left to right

metallic character decreases from left to right

Answer 2

Explanation:

a) number of shell remain same , while moving left to right in a period because period no decide the no of shell

b) it increases while moving left to right , becauses atomic no increase in a period , so to satisfy octet rule , it arrange atom in a particular manner

c) first it increase then decreases , because it depend on valence electron , if an element have 1 to 3 valence electron , it would have same valency , but if an element have 4 to 8 valence electron , it have to sub eg ( 8 - valence electron of an element)

d) size of atom decreases , because nucler effective charge increase , because in a period no of shell remain same but atomic no increase , therefore nuclues try to pull electron towards it

e)metallic character decreases because element lose their capacity to give electron and gain capacity to take electron

f) metals form basic oxide , due to decreases in metallic character it forms acidic oxide