Question

How many groups and periods are present in the modern periodic table?

Answer 1

Modern periodic table:

• The modern or long form of the periodic table is based on the modern periodic law which states that; the physical and chemical properties of the elements are the periodic functions of their atomic numbers.
• The modern periodic table is the present form of the periodic table in which the arrangement of elements is in the increasing order of their atomic numbers.
• The modern periodic table consists of $18$vertical columns also known as groups and $7$horizontal rows which are also known as periods.
• The modern periodic table showing the $18$ groups and $7$periods can be shown as;

Hence, there are $18$groups and $7$periods present in the modern periodic table.