Minute Mystery: a man is lying unconscious in the middle of a muddy field. No footprints at all are near him (not even his own), and there is nothing in.
Atom – the smallest unit of matter Helium atom.
REVIEW We can tell how many electrons and atom will gain or lose by looking at its valence. Metals like to lose electrons. (Cations) –Ex. Na + Nonmetals.
REVIEW
Ionic Formulas
