Question

2-Define group. How many groups are there in
Modern periodic table?
[1/2,1/2]​

Answer 1

In chemistry, a group (also known as a family) is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table; the f-block columns (between groups 3 and 4) are not numbered. ... Groups may also be identified using their topmost element, or have a specific name.

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