Task 1.4bi 

1. Draw the electronic configurations as 1s2, 2s2 etc and the electrons in boxes diagrams for the following atoms: 3Li, 5B, 10Ne, 14Si, 20Ca.

2. Explain which rules have been broken in the following incorrect configurations for sodium:
(a)

1s 2s 2p 3s 3p          
ih ih ihihi ih h

 

1s 2s 2p 3s 3p          
ih ih ihihii i  

 

1s 2s 2p 3s 3p          
ih ih ihihih   i

 

1s 2s 2p 3s 3p           3d             4s 4p      
ih ih ihihih       i