Both soap and detergent are some type of salts. What is the difference between them?
Describe in brief the cleansing action of soap. Why do soaps not form lather in head water?
List two problems that arise due to the use of detergents instead of soaps .

Explanation

Soaps are the sodium or potassium salts of long chain carboxylic acids while detergents are the ammonium or sulphonate salts of long chain carboxylic acids.
The dirt is oily in nature and when soap is added to water, its molecules form structures called micelles in which carbon chain of the molecules dissolves in the oil while the ionic end dissolves in water and faces outside. The micelles thus help in dissolving the dirt in water. (Note: 1 mark to be awarded if only labelled diagram of micelle is given) . `Ca^(2+)andMg^(2+)` present in hard water form insoluble substance (scum) with soap. Two problems : (i) Non-biodegradable (ii) Water pollution / soil pollution (Note: 1 mark to be awarded for any one of the problems.)