Ionic Compounds

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Ionic Compounds
Compounds can be broken into several categories.
The first type of compound we are going to study
are ionic compounds. Ionic compounds are made up
of substances known as ions. Ions are atoms that
have either lost or gained electrons causing them
to have a positive charge (lost electrons) or a
negative charge (gained electrons)
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We already know that positive and negative
charges attract. The attraction between a
positive ion and a negative ion is called an
ionic bond. Metals tend to lose electrons
becoming positive ions while nonmetals tend to
gain electrons becoming negative ions. Binary
ionic compounds are ionic compounds that contain
just two elements. Binary ionic compounds (1)
Are made up of positive and negative ions and
(2) Contain a metal ( ion) and a nonmetal (-
ion)
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What happens when a sodium atom collides with a
chlorine atom?
Since chlorine has the greater attraction for
electrons, it pulls the valence electron from
sodium and fills its outer energy level, forming
a stable octet. By gaining an electron, chlorine
becomes an anion with a -1 charge called a
chloride ion. By losing its valence electron,
sodium is left with a stable octet and becomes a
cation with a 1 charge called a sodium ion.
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The oppositely charged ions of sodium and
chloride attract each other very strongly. This
attraction causes an ionic bond to form. The
result of this ionic bond is the ionic compound
called sodium chloride. Since the compound
contains a single sodium ion and a single
chloride ion, the chemical formula for sodium
chloride is NaCl. Note the net (overall) charge
of an ionic compound is always zero. ie. 1
(-1) 0
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Show what happens when magnesium and chlorine
atoms collide using Lewis diagrams. Write the
formula of the compound that results and name it.