(TP, Ch 4)
Ionic Properties:
Ionic compounds:
 are composed of well-organized, tightly bond ions.
 are crystalline solids at room temperature.
 are hard, rough and brittle.
 have high melting points due to the attractions
between the positive and negative charges. (above
300°C)
 dissolve in water and conducts electricity
(electrolytes). Electrolytes are compounds that
conducts electricity when melted or dissolved in
water.
 KCl, CuSO4 , NaCl, NaHCO3
(salt sub., pools, salt, baking soda)

Representative Unit is a Formula Unit
Covalent Properties
Covalent Molecules:
 Composed of neutral atoms and held together by
strong bonds
 Weak intermolecular (interparticle) forces causes
them to be liquids or gases at room temperature.
 Do not conduct electricity in a pure state
 Many do not dissolve in water, some do (sugar);
generally less soluble in water
 Representative Unit is a Molecule
 Melting point – low (below 300°C)
**Table 16.5 p. 465(cp)** (transparency?)
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