Explain alkaline properties of detergent?

Answer 1

Soaps and detergents are based on having an organic acid attached to a long chain of carbon atoms. The problem with organic acids is that they do not form nice solids (they are more like thin pasty liquids) and they are not very water-soluble.

If you react the organic acid with a strong base like sodium hydroxide you can form the sodium salt of the organic acid. These sodium salts do form nice solids for pressing into cakes or powdering. And the sodium salts of organic acids are much more water soluble than their acid counter ion.

The down side is that all the free sodium in solution will tend to rip apart the water molecules to form a little sodium hydroxide. Thus the basic, or alkaline, nature.

But the basic nature assists in the cleaning action. One of the properties of a base is it ability to denature protein. In cleaning, the base is dissolving bits of skin and grease. It’s the alkaline nature that removes the ring around the collar.

http://en.wikipedia.org/wiki/Soap