Question

How to find the presence of 18 elements in 4 th period.

Answer 1

4th period in the periodic table has s-block , p-block& d-block elements…

hence max. no. of electrons accomodated by s, p & d sublevels = no. of elements in that period = 18 (2+ 6+10). ( a simple logic to remember )

hope you got it…

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