Section 8 consumer products Flashcards
What are soaps
They are molecules formed from an alkaline hydrolysis of edible fat or oil, with a hydrophobic tail and a hydrophilic head.
Alkaline hydrolysis equation
Fat molecule + alkali —-> soap + glycerol
Which alkali is typically used in alkali hydrolysis
Sodium
How many soaps does one fat molecule produce in alkaline hydrolysis
3 soaps + 1 glycerol
Soaps definition
A molecule with an ionic hydrophilic head and a non polar hydrophobic tail, formed from the alkaline hydrolysis of an edible fat or oil.
Molecules that soaps can remove
Non polar molecules due to the non Polar hydrophobic tail, which dissolves itself in the non polar molecules,
Cleaning action of soap
- The non polar hydrophobic tail will dissolve in the non polar substance.
- The ionic hydrophilic head will remain in the polar substance.
- When agitated the non polar molecules break apart into smaller globules.
- These tiny globules with their negative ions repel each other and are then easily washed away.
Hard water
Water that contains high concentration of magnesium and calcium ions.
How is hard water formed
Through ions being dissolved out of the soil by rainwater and into drinking supplies.
Scum definition
A precipitate formed between a soap and hard water.
Lather
Where large group of molecules break down into tiny globules due to the use of a soap and agitation.
Soapless detergents
Detergents are molecules with a non polar hydrophobic tail and an ionic hydrophilic head, which don’t form scum in hard water.
Advantage of detergents over soaps.
Detergents don’t form scum in hard water.
Difference in the structure of detergents and soaps
The structure of the negative ion is different, detergents : S=O=O O- soaps C=O O-
Emulsion
Where a non polar liquid and polar liquid have tiny droplets dispersed in each other.
How are emulsifiers formed
Edible oils + 2glycerol —> emulsifier
Emulsifiers structure
A glycerol molecule with 1 or 2 fatty acid chains.
How do emulsifiers work
The free hydroxyl groups remain in the polar molecule, and the fatty acid hydrophobic tails dissolves in the non polar substance and keeps them dispersed in each other.
