Question

Discuss briefly the modern periodic table

Answer 1

• Dmitri Mendeleev was a Russian chemist and inventor. He is being the creator of the first version of the modern periodic table
• The modern periodic table was discovered by Henry Moseley
• It is based on the atomic number of elements
• Modern periodic table contains 7 horizontal rows called periods and 18 vertical columns called groups.
• The First period contains only 2 elements, this is the shortest period
• The sixth period contains 32 elements this is the longest period.
• Elements of group 1 are called alkali metals
• Elements of group 2 are called alkaline earth metals
• In a group from top to bottom, atomic size increases.
• In a period from left to right, atomic size decreases, and effective nuclear charge increases
• The periodic table is divided into four main blocks. s-block, p-block, d-block and f-block.

Block	Elements
s -block	group 1 and 2
p block	group 13 to 18
d block	group 3 to 12
f block	Lanthanides and Actinides

Modern periodic law

Modern periodic law states that the physical and chemical properties of the elements are periodic functions of their atomic number.