CHAPTER 3
ACIDS AND BASES
INTRODUCTION
The Oldest Theory: Arrhenius Theory
You should be familiar with this one from
your earlier chemistry courses in high school.
Arrhenius looked at the substances which
were called acids. Some of these substances
were known from even before the days of
alchemy.
They taste sour, turn blue litmus to red,
neutralize bases, release hydrogen gas when
added to an active metal and release carbon
dioxide when added to a carbonate.
Arrhenius said these properties were due to
the production of H+ions when acids dissolve
in water.
Today we know that a bare proton does
not exist in water, it forms a chemical
bond with a water molecule forming the
H3O+. This ion is called the hydronium
ion.
He looked at the properties of bases.
They taste bitter, feel slippery (soapy),
turn red litmus blue and neutralize
acids.