Question

Metallic character and non-metallic character are periodic properties discuss ?

Answer 1

The periodic variation in electronic configuration as one move sequentially in increasing order of atomic number produces a periodic variation in properties.
As the elements are arranged in increasing order of atomic number, the metals with tendency to lose electrons are placed on the left and the metallic character decreases from left to right and increases down a group and non-metals with tendency to gain electrons are placed automatically on the right and the non-metallic character increase across a period and decreases down a group.