2. 7 valence electrons
3. u did it right
1. They are hard and malleable, they can dissolve in water, they are good conductors of electricity, and they have high melting and boiling points.
2. A metal and a nonmetal is involved in ionic bonding.
3. The dots in the electron dot formula represent the valence electrons
4. The valence electrons are only shown in the electron dot formula because the chemical reactivity of an atom of an element is mainly determined by the number of its valence electrons.
Hope it helped!