Chemistry Reference
In-Depth Information
5. Making Soap
Topic
Basic soap can be made from oils and sodium hydroxide, then
personalized with fragrant oils.
Introduction
Hundreds of varieties of soap can be found in your local pharmacy or
grocery store. Products range from abrasive industrial soap to colorful and
decorative soaps that are shaped in molds and liquid soap sold in pump
bottles. Until the early 20th century, soap was almost entirely made at
home using animal fats and a strong base called
lye
(sodium hydroxide)
that was obtained from wood ash. The industrial production of soap began
after World War I. At that time, fats were in short supply, so vegetable oils
were used. Today, some people still choose to make their own soap so
that they can select the properties of that soap.
The process of making soap is a type of neutralization reaction known
as
saponification.
. Neutralization is important because, without it, the
acids and bases in soap would be dangerous to handle. In a
neutralization
reaction
, an acid and a base react to form water and a neutral substance
called a
salt
. Neutralization makes the acids and bases safe to use.
Saponification requires a reaction between a slightly acidic oil and a very
strong base to produce a salt with unique cleaning properties.
Soap can have different characteristics and qualities depending on the
oils used to create it, as well as the scents, colors, and other additives
that can be mixed in before the soap hardens. In this experiment, you
will choose a combination of oils, colors, and fragrances and create soap
using the process of saponification.
Time Required
45 minutes
