• Oil, greasy organic substances found in living organisms
• Insoluble in water (because water is very polar)
• Soluble in organic solvents (benzene, chloroform (trichloromethane), diethylether
(ethoxy ethane)).
• No common chemical structure

• Fats and oils – obtained from natural sources; important source of energy
• Phospholipids – water insoluble components which biological membranes are constructed.
• Glycolipids – lipids attached to a sugar; energy storage and cell recognition
• Steriods – chemical messengers

• Esters of glycerol and predominantly longchain fatty acids (carboxylic acids)

• Fats and oils are esters of glycerol and predominantly long chain fatty acids.

• Fats and oils are esters of glycerol and predominantly long chain fatty acids.
Ester Functional Group Long Chain Fatty Acids

• Fats and oils are called triacylglycerols or triglycerides since each molecule is derived from one molecule of glycerol and three molecules of fatty acid.
General formula of a triacylglycerol.
Typical triacylglycerol: contains 3 fatty acids.

• Vary in 3 ways…
1) length of fatty acid chain can contain between 4 and 20 carbons, but carbon number is almost always even
2) Can be saturated or unsaturated
3) May contain three different fatty acids

18 carbon chain length
1 double bond oleic acid linoleic acid
18 carbon chain length
2 double bonds

• The human body can produce all but two fatty acids: Linoleic, alpha-Linolenic (Omega 3 and
Omega 6)
• These must be supplied in the diet.
• Impaired growth and reproduction
• Eczema and dermatitis.

• Fats are solid at room temperature.
• Fats contain a higher proportion of saturated fatty acids.
• Oils are liquid at room temperature.
• Oils contain higher amounts of unsaturated fatty acids.
• Polyunsaturated means that the molecules of a particular product each contain several double bonds.
• Monounsaturated and polyunsaturated fats are better for humans than saturated.

Soap is made by hydrolyzing fats or oils with aqueous NaOH or KOH.
This is called saponification.

• When a triglyceride is reacted with KOH (potassium hydroxide) or NaOH (sodium hydroxide or lye) a soap is formed and glycerol.
• Triglycerides are esters.
• The base hydrolyzes the ester into soap and glycerol.
• This is known as saponification.
• If the soap is a sodium salt, it is a “hard soap”.
• If the soap is a potassium salt, it is a “soft soap”.

Example of a “hard soap” :

• Very long chain
• One end is polar and the other is nonpolar
• Polar end orients itself toward polar water
• Nonpolar ends orient them selves toward one another and trap grease and oil

Wikipedia

• Liposome is spherical and contains a lipid bilayer (2 layers)
• Micelle is also spherical, but contains a lipid monolayer (1 layer)
• Can also have a bilayer sheet.

• Emulsify means combining two liquids together which normally don't mix easily.
• Iron (III), calcium and magnesium create an insoluble salt which does not have the same emulsification properties as soap made with potassium and sodium.
• Addition of phosphate solves this problem but causes another pollution problem, eutrophication.
• Eutrophication – fish and other organisms are killed due to insufficient oxygen

• LAS - Linear alkyl sulfonates – sodium salt of an alkylbenzenesulfonate.
– Biodegradable
– Non-branched side chain
– Soft detergent, less foam
• ABS - Alkylbenzene sulfonates
– Not biodegradable
– Branched side chain
– Hard detergent, no longer used in US
• SDS – a sodium alkyl sulfates
– Sodium dodecyl sulfate
– Very common detergent (major ingredient in carpet shampoos)

• Continual boiling of a solution in a vial or flask
• Solvent is continually returned to the reaction vessel from a condenser atop the vial or flask
• Ethanol has a low boiling point and would easily evaporate from the reaction flask without a condensor
• A common technique for carrying out organic reactions
• Reaction mixture can be heated to boiling without solvent loss.

Wikipedia
Heating
Mantel

• Day 1: Synthesize soap via reflux and then cooling!
• Day 2: Testing various properties of your soap
– Tube #1 = DI water (negative control),
Tube #2 = your Soap,
Tube #3 = Detergent (positive control)
– Tests
• Emulsification
• Heavy metals
• Acidity
• Unsaturations

• Addition of Bromine across double bonds.
• Test for unsaturations
• Yellow/Orange to Clear