Ion: an electrically charged atom or group of atoms
Molecule: a neutral group of atoms joined by covalent bonds
Ionic Compounds
 Ionic bonds (between two
oppositely charged ions)
 Form between metals and
Molecular Compounds
 Covalent bonds (atoms share
valence electrons)
 Form between two nonmetals
nonmetals
 Ionic Bonds – very strong
 Covalent bonds – weak
 High melting point
 Low melting points and boiling
points
 Conduct electricity when
 Poor conductors of electricity
dissolved in H2O
 Form hard, brittle crystals
 Ex: NaCl (table salt)
 Ex: H2O
C12H22O11 (sugar)