5.1, we learned that compounds which have ionic bonds are called ionic compounds.
In section 5.1.3, we
learned that in aqueous solution, an ionic compound dissociates into its ions
and giving the solution the ability to conduct electricity. Any substance that
gives ions in an aqueous solution and thereby conducts electricity is called
As an ionic solid such as
NaCl dissolves in water, water molecules must overcome the forces which hold
ions together to make them go into solution. The polar water molecules are attracted
to both positive and negative ions of the ionic solid.
Look carefully at the above
diagram and see that the positive ions are attracted by the oxygen atom of the
water and the negative ions are attracted by the more positive hydrogen atoms
of water. Once an ion is surrounded by the water molecules,
an ion is freed from the lattice and a hydrated ion