Question

element- N, O, C, B. atoms radii - 74, 66, 77, 88. now que 1. in which period does these elements lies. and 2 que arrange these elements in the increasing order of their atomic number. give reason for your answer.

Answer 1

Nitrogen(N) :

Z = 7 

Electronic configuration : Is²2s²2p³ 

As the last electron lies in 2nd shell so it belongs to 2nd period 

Oxygen : 

Z = 8 

Electronic configuration : Is²2s²2p⁴

As the last electron is in 2nd shell so it also second period element 

Carbon : 

Z = 6 

Electronic configuration : 1s²2s²2p²

Period = 2nd 

Boron : 

Z = 5 

Electronic configuration : Is²2s²2p¹

Period = 2nd 

Increasing number of their period 

B<C<N<O

Answer 2

the answer is attached below