Question

How many periods and groups are there in the Modern Periodic Table?

Answer 1

Groups:

• There are 18 vertical columns in the modern periodic table.
• Each column is called a group.
• The groups have been numbered from 1 to 18 (in Arabic numerals) from left to right.
• Group 1 in the extreme left position contains alkali metals (Li, Na, K, Rb, Cs, and Fr) and group 18 in the extreme right side position contains noble gases (He, Ne, Ar, Kr, Xe, and Rn).

Periods:

• There are seven rows in the modern periodic table.
• Each row is called a period.
• The periods have been numbered from 1 to 7 (Arabic numeral)
• In each period a new shell starts filling up. The period number is also the number of shells that starts filling up in it.