Q5 of 55 Page 1

State the modem periodic law for classification of elements. How many (i) groups and (ii) periods are there in the modem periodic table?

According to the modern periodic law:

For classification of elements, the elements were arranged according to the increasing atomic number which gave modern periodic table.


(i) It has 18 vertical columns known as Groups


(ii) It consists of 7 horizontal rows knowns as Periods = 7


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