SAPONIFICATION
Polymers
SAPONIFICATION
The making of soap from
a fat or oil and a
caustic material such
as lye or sodium
hydroxide
SOAP MOLECULES
HAVE
BOTH
A POLAR
HEAD
&
A
NONPOLAR
TAIL
POLARITY OF SOAP MOLECULES
POLAR HEADS
– WATER- LOVING
– HYDROPHILIC
– COMPOSED OF
CHARGED OR
PARTIALLY CHARGED
PARTS
NONPOLAR TAILS
– WATER-FEARING
– HYDROPHOBIC
– COMPOSED OF A LONG
UNCHARGED
HYDROCARBON CHAIN
“LIKES DISSOLVE LIKES”
WATER
IS A
POLAR SOLVENT.
IT WILL DISSOLVE
POLAR SOLUTES
TO MAKE A
HOMOGENEOUS
SOLUTION.
PARTIALLY NEGATIVE OXYGEN
PARTIALLY POSITIVE HYDROGENS
(polar molecules are called dipoles)
“LIKES DISSOLVE LIKES”
HEXANE
IS A
NONPOLAR SOLVENT.
IT WILL DISSOLVE
NONPOLAR SOLUTES
TO MAKE A
HOMOGENEOUS
SOLUTION.
NONPOLAR HEXANE
UNCHARGED
HYDROCARBON
CHAINS
POLAR AND NONPOLAR ARE IMMISCIBLE
POLAR VINEGAR
WILL NOT MIX
WITH
NONPOLAR OIL.
THE MIXTURE
REMAINS
HETEROGENEOUS.
SURFACTANT ACTION
SOAP MOLECULES ARE SURFACTANTS, SURFACE SEEKING.
IN A BEAKER OF POLAR WATER, SOAP
MOLECULES SEEK THE SURFACE.
Polar heads of soap molecules face toward polar water
and nonpolar tails stick out.
water surface
SURFACTANT ACTION
SOAP MOLECULES ARE SURFACTANTS, SURFACE SEEKING.
IN A BEAKER OF NONPOLAR HEXANE,
SOAP MOLECULES SEEK THE SURFACE.
Nonpolar tails of soap molecules face toward
nonpolar hexane and polar heads stick out.
hexane surface
HOW DOES SOAP CLEAN?
CONSIDER THE ENVIRONMENT:
AQUEOUS POLAR
MEDIUM
NONPOLAR DIRT
OR OIL
UNIQUE QUALITY OF SOAP
MOLECULES
=
GREASE OR DIRT
THE SOAP MOLECULES CAN
SURROUND NONPOLAR DIRT OR
GREASE WITH THE POLAR HEADS
POINTING OUT TOWARD THE
POLAR AQUEOUS MEDIUM AND
THE NONPOLAR TAILS STICKING
INTO THE DIRT OR GREASE. THE
RESULTING STRUCTURE IS
CALLED A MICELLE.
MICELLE FORMATION
This is a micelle. The
interior green portion of
the cluster is composed
of hydrophobic nonpolar
parts and the exterior is
composed of hydrophilic
polar parts.
CLEANING ACTION OF SOAP
In cleaning, the nonpolar ends
of soap molecules attach to
nonpolar grease or dirt, letting
water seep in underneath.
The grease or dirt is pried loose
and surrounded by soap
molecules with the polar ends
facing out.
The micelles are then carried off
by a flood of polar water.
Classzone has a 30 second clip of micelle
formation.
micelle formation
SAPONIFICATION:
THE CHEMICAL REACTION
`
OIL AND LYE  SOAP AND GLYCEROL
THIS IS THE OVERALL REACTION!!!!!!
THE ASSESSMENT IS ON:
• THE EQUIPMENT
AND PROCESSES
USED IN THE
LABORATORY
• HOW SOAP
CLEANS
CLOTHES, HAIR,
SKIN AND DISHES
• THE STRUCTURE
AND FUNCTION OF
SOAP MOLECULES
• THE BOOK
MATERIAL, PPT
NOTES AND
EDMODO VIDEOS
DISCUSSION QUESTIONS
• Soap was expected as the product in this reaction.
Explain how the properties of the lab product are
consistent with commercial soap.
• Describe the differences in the bubbles of the three
soaps. Which soap bubbled the least and how would
this be beneficial to its function?
• Describe the differences in the pH of the three soaps.
Which soap had the pH farthest away from neutral
(7)? Would you use this soap to wash your hair and
face? Explain.
DISCUSSION QUESTIONS
• Describe the results of adding calcium,
magnesium and iron ions to the soap solutions.
The same phenomenon occurs when hard water
and well water are used to wash hair, skin and
clothes. In fact, the shower and tub also suffer.
Explain.
• What are several reasons for error in this lab?
Explain how each of these reasons impacts the
results in this lab.