Question

There are 18 groups (vertical columns) and 7 periods (horizontal rows) in Modern

periodical table. Elements in same group have same number of valence electrons.

Elements in same periods have same number of shells. Position of elements in

periodic table can predict its valence electrons, valency, size, reactivity.

Given below are the electronic configuration of some elements:

a) A-2,8,3 b) B- 2,8,1 c) C-2,8,7 d) D- 2,8,8 e) E- 2,1 f) F- 2,8,4

i) Which elements belongs to same group:

a) A and E b) B and E c) C and D d) A and F.

ii) Which of these is a halogen:

a) C b) B c) A and C d) D

iii) Which of these is an inert gas:

a) D b) C c) B d) A

iv) Which of these element shows the property of catenation:

a) A b) B c) F d) D​

Answer 1

Answer:

electonic configuration of some elements are

a) Aluminum

b) Sodium

c) chlorine

d) Argon

e) lithium

f) Silicon

i) A and F

ii) C

iii) D