What are the sublevels in an energy level of n=3?

Nonmetal halogen family atmoic mass 35

Compare and contrast physical changes with chemical changes.

Which of the following observations indicates that there is a small, dense, positively charged part in the center of an atom? some uncharged particles are scattered by a gold foil. all uncharged particles are attracted towards a gold foil. all positively charged particles pass straight through a gold foil. some positively charged particles bounce back from a gold foil.