Question

The modern periodic table contains ___________ groups.

Answer 1

Modern periodic table:

• “The physical and chemical properties of the elements are periodic functions of their atomic numbers”
• The horizontal rows are called periods while the vertical columns are known as groups.
• “According to the recommendation of the International Union of Pure and Applied Chemistry (IUPAC), the groups are numbered from 1 to 18 replacing the older notation of groups IA … VIIA, VIII, IB … VIIB, and 0”.
• There is a total of seven periods. The period number is the highest principal quantum number (n) of the elements in the period.
• Group 1 is identified as Alkali metals while Group 2 is Alkaline earth metals.
• Group 17 is known as the Halogen family while the elements of Group 18 are Noble gases.
• d and f block elements are transition and inner transition elements respectively.
• 

The modern periodic table contains 18 groups.