matter , masss , interconversion , fluids , atoms , molecules , intermolecular force , intermolecular space , physical change , chemical change , desirable change , undesirable change , exothermic change , endothermic change , reversible change , irreversible change , melting , frezzing , boiling , sublimation , eveporation , dissolving , digestion , respiration , burning , rusting , curdling , photosynthesis, pure substance , mixture , element , compound , homogenous mixture , heterogeneous mixture , ions , distillation , fractional distilattion , sepearting funnel , sublimation , paper chrmatography , electrons , proton , neutrons , shells or orbit , nucleons , radicals , monoatomic , diatomic , triatomic and polyatomic molecules , valency , valence electrons , variable valencies , periodic table