1. Polarity of Solvents
Background Information for Soap Lab

2. A Hydrocarbon Typical petroleum product Non-polar
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 470

3. Oil and Water Don’t Mix Oil is nonpolar Water is polar
“Like dissolves like”
Lycopodium Powder demonstration.
Lycopodium powder is a nonpolar hydrocarbon that doesn’t mix with water. It is dry to the touch and not oily feeling. Sprinkle lycopodium powder on top of a beaker of water. Slowly, puch your finger through the surface of the lycopodium power into the water. Slowly withdraw your finger, it remains dry the entire time. Why?
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 470

4. Hydrogenation + H2 shortening stick margarine tub (soft) margarine
vegetable oils
+ H2
FOOD SUBSTITUTES
“Chemistry is widely used in the food industry to manufacture new convenient foodstuffs and to check for impurities. Butter is known as a saturated fat, whereas most vegetable oils, which are normally liquid, are polyunsaturated fats. They can be changed to solids, such as margarine, by a chemical process called hydrogenation – the addition of hydrogen to the oils using a catalyst. Hydrogenation makes the oil more like butter and easier to spread. Margarine was first developed in the 1860’s in France as a cheap butter substitute.”
Eyewitness Science “Chemistry” , Dr. Ann Newmark, DK Publishing, Inc., 1993, pg 7
Timberlake, Chemistry 7th Edition, page 570

5. Molecular Polarity H nonpolar molecules: -- e– are shared equally
H–C–H H
nonpolar molecules: -- e– are shared equally
-- tend to be symmetric
e.g., fats and oils H O
polar molecules: -- e– NOT shared equally
e.g., water
“Like dissolves like.”
polar + polar = solution
nonpolar + nonpolar = solution
polar + nonpolar = suspension (won’t mix evenly)

6. Using Solubility Principles
Chemicals used by body obey solubility principles.
-- water-soluble vitamins: e.g., vit. C
-- fat-soluble vitamins: e.g., vits. A, D
Dry cleaning employs nonpolar liquids.
-- polar liquids damage wool, silk
-- also, dry clean for stubborn stains (ink, rust, grease)
-- tetrachloroethylene is in common use
C=C Cl

7. MODEL OF A SOAP MOLECULE
emulsifying agent (emulsifier):
-- molecules w/both a polar AND a nonpolar end
-- allows polar and nonpolar substances to mix
e.g., soap
detergent
lecithin
eggs
MODEL OF A SOAP MOLECULE
Na1+
NONPOLAR
HYDROCARBON
TAIL
POLAR
HEAD

8. A 20 mule team hauling borax in Death Valley
Soap Making
A 20-mule team hauling borax out of the valley. Photo provided by the National Park Service.
Borax (Na2B4O7 _10H2O), the most widespread borate mineral was found to help remove dirt from people and cloth. Borax is crumbly and powdery, and dissolves easily in water. Borax became an alternative to the very harsh soap which was used prior to the discovery of borax in the late 1800's. This light and easy to use substance was hailed the world over as a washing, cleansing, antiseptic, preservative, and medicine miracle.
In the 1880s, large borate deposits were discovered in Death Valley, California. However, the Death Valley borate deposits were located almost 170 miles from the nearest railway. In order to get the borate to the railway economically, the owners of the Death Valley mines used large wagons pulled by teams of 20 mules. The detergents made from this borate were thus sold as "20 Mule Team Borax". 
                                                                                         A 20 mule team hauling borax in Death Valley

9. Soap Article Soap Article ChemMatters Feb. 1985 Questions Soap Article
The Story on Suds
(8 min 19 sec)
Keys

10. Saponification 3 sodium palmitate (soap) Glyceryl tripalmitate
SOAP MAKING
Saponification is the process of making soap from fat. The chemical reaction for this is shown in the slide.
3 C19H37O NaOH > C18H35O21- Na C3H8O3
glyceryl tristearate (fat) sodium hydroxide sodium stearate (soap) glycerin
Read Chem Matters “Soap Making”
3 sodium palmitate
(soap)
Glyceryl tripalmitate
(tripalmitin)
Glycerol

11. A Phospholipid
Timberlake, Chemistry 7th Edition, page 576

12. Stearic Acid Fatty acid Carboxylic acid group Soap
COO- bonds to a metal ion (Na+)
Na+
H+ lost from COOH
Kelter, Carr, Scott, Chemistry A Wolrd of Choices 1999, page 257

13. Cleaning Action of Soap
Micelle
Timberlake, Chemistry 7th Edition, page 573

14. SOAP vs. DETERGENT
-- made from animal and -- made from petroleum
vegetable fats -- works better in hard water
Hard water contains minerals w/ions like Ca2+, Mg2+, and Fe3+ that
replace Na1+ at polar end of soap molecule. Soap is changed into
an insoluble precipitate (i.e., soap scum).
micelle: a liquid droplet covered
w/soap or detergent molecules

15. Solvation
“Like Dissolves Like”
NONPOLAR
POLAR

16. Solvation Soap / Detergent polar “head” with long nonpolar “tail”
dissolves nonpolar grease in polar water
micelle

17. Lab - Soap Making Lab: SOAP making Lab: SOAP making Keys

18. A Model of a Cell Membrane
Polar
Nonpolar
Cholesterol
Proteins
Phospholipid
bilayer
Timberlake, Chemistry 7th Edition, page 587

19. Formation of a Triglyceride

20. Lava Lamp It is… a philosophy once ruled our world an art form
progressive
post-modern
here to stay

21. Lava Lamp It is… a philosophy the primordial ooze once ruled our world
Polar mixture H
H-O-C-C-O-C-C-O-C-C-O-C-C-O-H
Water
the primordial ooze
Polyethylene glycol
once ruled our world
the moment
Nonolar mixture Cl H
H-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-H
an art form
Chlorinated paraffin
Paraffin from kerosene
a classic
Heat transfer coil
progressive H
H-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-H
prehistoric
Bulb gives heat and light
post-modern
here to stay