How Does Soap Work?
Soap acts as an emulsifier, meaning that it allows one substance to be dissolved
into another, into which it would not dissolve otherwise. Soil contains grease and oil,
which are not water-soluble; however, soap attaches itself to the grease molecules,
loosens them, and allows them to dissolve in water, and be rinsed away.
There are three types of energy which must be present in order for soap to work
well: chemical energy, thermal energy, and kinetic energy. The chemical energy is
provided by the soap, and allows soil that can’t be removed with just water to be
loosened from the soiled surface, and suspended within the soap molecules. Thermal
energy is provided by using warm or hot water. The third type, kinetic energy, is
created by movement – washing machine agitation, or old-fashioned elbow grease.
If any of these elements are missing, the cleansing process will not be as effective;
for example, soaking soiled clothing in soapy water, without scrubbing or agitating it,
will not get it as clean as if it were put in the washer. Similarly, attempting to remove
soil with only water, and no soap, is likely to be ineffective.
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