Soaps, Detergents And Emulsions Flashcards
What is a soap?
A soap is the salt of a carboxylic acid.
Give features of soaps:
- Soaps molecules long, non-polar hydrocarbon chains.
- Soaps have a polar head and a non-polar tail.
- They have an ionic (hydrophilic) head which is water soluble.
- They have a hydrocarbon (hydrophobic) tail which is soluble in oil and grease.
Why is meant by the term hydrophobic?
Does not dissolve in water
What is meant by the term hydrophilic?
Dissolves in water
What are detergents?
Detergents are compounds with a soap like structure which allows them to remove greasy stains.
What is the difference between a detergent and a soap?
The main difference between a soap and a detergent is the head.
- The head part of a detergent will always be soluble in water and this can be achieved by using heads which are negative ions, positive ions or have an overall polar structure.
- The detergent head will never be formed from a carboxylate ion whereas soaps contain a carboxylate ‘head’ formed from the reaction of the carboxyl group with the base.
- Detergents, unlike soaps, will not form precipitates in hard-water areas.
What is meant by the term hard water?
Hard water is when the water is rich in dissolved calcium and magnesium ions.
What happens when hard water is mixed with soap?
When hard water is mixed with soap, instead of forming a soapy lather, a precipitate is formed.
What is an emulsion?
- An emulsion is a liquid which contains small droplets of another liquid, such as soapy grease particles mixed in water.
- Emulsions of oil and water are commonly found in food.
What is an emulsifier?
Emulsifier is a compound which allows oil and water to mix.
What are emulsifiers used for?
Emulsifiers are used to keep water-soluble and oil-soluble compounds together.
