Question

Explain any 5 characteristic of periods and groups.
a) Valance electron
b) Valancy
c) Size of atom
d) Metallic character
e)Chemical reactivity.​

Answer 1

Answer:

1. valance electron:a single electron or one of two or more electron in the outer shell of an atom that is responsible for the chemical properties of the atom.
2. valancy:a combine capacity of a atom known as valancy