Question

Element A and B have atomic number 13 and 27. Write their electronic configurations and predict their period, group and block. Which of them is a transition element?​

Answer 1

Explanation:

Given -

• Atomic number of A is 13 and B is 27

To Find -

1. Write their Electronic configuration
2. Predict group, period & block
3. Which of them is a transition element ?

Solution -

Element A = 13

Electronic configuration = 1s² 2s² 2p⁶ 3s² 3p¹

Element name = Aluminium

Symbol = Al

Period = 3

Group = 13

Block = p-block

And

Element B = 27

Electronic configuration = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d^7

Element Name = Cobalt

Symbol = Co

Period = 4

Group = 9

Block = d-block

Therefore,

Element B (Co) is a transition element.