2.5 Soaps, Detergents and Emulsions Flashcards
How are soaps produced
By the hydrolysis of fats and oils
What is the structure of a soap
Hydrophilic head and hydrophobic head
What happens when soap is added to water
It forms a colloidal suspension
When would a detergent be used
Where hard water is present
What is hard water
Water that contains dissolved Ca2+ and Mg2+ ions and so can form precipitates (scum) with regular soap
Why are detergents useful in areas where hard water is present
They do not react with Ca2+ and Mg2+ ions and so do not form precipitate
What are detergents used for
Washing clothes, dishes
What are detergents derived from
Crude oil
What is an emulsion
When 2 immiscible liquids are added together and vigorously shaken an emulsion is formed
Give an example of an emulsion
Greasy soap molecules mixed in water
How are emulsions in food made
By reacting edible oils with glycerol to form molecules in which either 1 or 2 fatty acid groups are linked to a glycerol backbone rather than 3
Give an example of an emulsion in food
Milk, Mayonnaise
How does soap help bring grease and water together
The two layers would usually separate but soap acts as an emulsifier and helps bring the substances together
What process is used to produce sodium salts of fatty acids
Alkaline Hydrolysis
