Question

Explain modern periodic table briefly in understanding manner?

Answer 1

It is proposed by Henry Moseley in 1913. He placed the elements in increasing atomic number (Modern periodic law). There are 7periods and 18 groups. When we ho down the group size of elements increases due to increases of a new orbital but when move left to right size decreases it is due to increase of nuclear charge which attract towards nucleus.

Answer 2

Modern perodic table is nothing but a modified form of madleve's perodic table it is Hendry Mosley who purpose the idea that it is better to arrange elements in increasing atomic number instead of increasing atomic mass in modern perodic table no gaps where left all the predicted gaps of Mandelve where filled and all the elements are arranged in a specific pattern.