Answer:
Phosphorus has a low melting point because the intramolecular forces holding it together is London Dispersion Forces.
Explanation:
London Dispersion Forces (LDF) are the weakest intramolecular forces. You don't need to break the covalent bonds, but rather the Van Der Waals' Forces. If LDF are the weakest forces, then the melting point is low.
Rutherford's gold foil experiment proved that there was a small, dense, positively charged nucleus at the center, which contained most of the mass of the atom. Which contained electrons orbiting the nucleus.
Here is a picture of which shows you how many valence electrons are in the Lewis structure of xeo4
