How does detergent get our clothes clean?

Anionic surfactants are the workhorse ingredients of most
washing detergents. They are compounds such as sodium
alkyl sulphate and are made up of molecules that have
opposite charges at diff erent points (polar molecules). Water is also
made of polar molecules and, when mixed with washing detergent,
the hydrophilic (water-loving) part of the surfactant molecule
attracts to the water molecule, while the hydrophobic (waterhating)
part of the molecule adheres to the dirt and grease in
your clothes. This makes the dirt and grime more soluble in
the water, allowing for easier removal from your clothing.
Another cleaning eff ect surfactants have is to lower
the surface tension of water. Surface tension is created
by these polar molecules pulling on one another due to
their charge. This accounts for how pond skaters walk
on water and why beads of water hang on grass. By
lowering surface tension, the water can become more
‘wet’ and permeate clothes better