Question

the incompletely filled period is

Answer 1

18 TH group of periodic table

Answer 2

Answer:

the incomplete period is VII A or 17th period

Explanation:

VII A group consists of

1. Florine

2. Chlorine

3. Bromine

4. Iodine

5. Astatine

6. Tennessine

These all elements need 1 electron to become stable.

If we check on all the groups VIII A group is the most stable and every element tend to become like them.

The nearest group to VIII A group is the VII A group so, VII A or 17th group is incompletely filled and has more electro-negativity than all the groups in the periodic table