Question

When elements are placed in the order of their increasing atomic number,
the elements having the same number of __________ is repeated in such a way, so as to fall under the same group. Since, the electronic configuration of the valence shell electrons is same they show similar properties.

• A. valence shell electrons
• B. inner electrons
• C. electrons present in inner shell
• D. protons and neutrons

Answer 1

The correct option is A valence shell electrons

When elements are placed in the order of their increasing atomic number,the elements having the same number of valence shell electrons is repeated in such a way, so as to fall under the same group. Since, the electronic configuration of the valence shell electrons is same they show similar properties
Hence option A is correct.