Characteristics of a group:
1. Valence electrons → All elements show same valence electrons in a group.
2. Valency → Valency of all the elements remains the same in a group.
3. Atomic size → The atomic size goes on increasing down the group.
4. Metallic character → In case of metals the metallic character increases down the group.
5. Non-metallic character → In case of non-metals the non-metallic character decreases down the group.
