Question

how to determine the place of an atom in the periodic table using electronic configuration. please explain with example.

Answer 1

Let's take an example of Potassium ;

Electronic Configuration
= 1s2 2s2 2p6 3s2 3p6 4s1

The last last pair of electrons is in the orbit

4s1

Then :
The Period it belongs to = 4
The block it belongs to = s
No. of Valence electrons in the last shell = 1
Hence it's Valency is 1
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Like this example ,the position of the and element can be determined by the position of its last pair of electrons. That is in which orbital it belongs to.



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