1. 118
2. It consists of the elements oxygen (O), sulfur (S), selenium (Se), tellurium (Te), and polonium (Po). synthetic elementlivermorium (Lv)
3.same number of valence electrons
4. 8 because it has full valence shell
5. Halogens are the compounds found in group 17 of the periodic table. They are all incredibly electronegative, meaning that they are very willing to take electrons from other atoms. Fluorine, for example, is the only element that can take electrons away from oxygen.
Alkali metals, on the other hand, are just the opposite: Their electronegativity is very low, meaning that they are very willing to give away electrons
Both groups are highly reactive.
6. atomic number is the number of protons
7. a Columb of elements in a periodic table
8. a row of elements in the periodic table