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Many chemicals are used in a laboratory. These chemicals
are classified as either acids, bases or salts. What
are acids? The word `acid' is Latin for `sour'. The
three commonly used acids in the laboratory are
hydrochloric acid, sulphuric acid and nitric acid.
Nature also has an abundant supply of acids. For
example, citric acid can be found in fruits and
vegetables such as lemons and oranges. Malic acid is
found in apples, tartaric acid in grapes and oxalic acid
in rhubarbs. Acids are also formed in the bodies of
human beings and animals. Lactic acid accumulates in our
muscles when we exercise.
All acids have certain common properties. Acids have
an unpleasantly sour taste. They turn blue litmus paper
red and change methyl orange solution from orange to
red. Acids react with alkalis to form neutral compounds
known as salts.
Acids are important chemicals and are used in
countless industrial processes such as the manufacture
of fertilizers, drugs, plastics, dyes and explosives.
Among the more important and useful acids are
sulphuric acid, hydrochloric acid, nitric acid and
acetic acid. The first three acids are known as mineral
acids since they are found in the earth. Acetic acid is
an organic acid as it is found in living things.
Sulphuric acid is also known as oil of vitriol. It is
the most widely used acid. It is a component of
fertilizers called super-phosphates. It is also used in
the preservation of perishable foodstuff and in
batteries for motor vehicles.
Hydrochloric acid is used to clean steel plates
before they are coated with tin to make tin plates. It
is also used for dyeing and making glue.
Nitric acid is essential in the manufacture of
explosives. It is also used to dissolve metals. Nitric
acid is used for etching, a process whereby a design is
made on a metal plate and acid is used to eat away part
of the surface. The resulting plate is used for
printing.
It is acetic acid which makes vinegar sour. Acetic
acid is used in various chemical processes such as
making acetone, which is the basic ingredient of paint
removers.
Knowledge about acids and how they can be utilized
has benefited mankind tremendously and made life much
easier for us. |
