How many valence electrons does the lewis structure for a chlorine atom show?

7 valence electrons. Hopefully that's right

Polyethylene is a strong synthetic polymer that can be used to make toys and bottles. polyethylene is a plastic material called thermoplastic. one very useful property of thermoplastic is that when it is heated it turns into liquid, which can be molded into desired shape and size. also the material do not dissolve at room temperature.

Van der waals forces are temporary electromagnetic forces established between uncharged atoms. some neutral molecules, when close together, can become temporarily “charged,” as electrons move around the atom. water is a polar molecule, the side of the molecule that the hydrogens bond to being more positive, and the opposite side bound to the lone pairs of electrons being more negative. this means that it participates in dipole-dipole interaction (non-polar exhibits dispersion forces), and it has the capacity for hydrogen bonding.