polarity of solvents. a hydrocarbon typical petroleum product non-polar ch 2 ch 3 ch 2 ch 3 c 18 h...
TRANSCRIPT
A Hydrocarbon
• Typical petroleum product
• Non-polar
CH2 CH2
CH2CH3 CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH3
C18H38
Oil and Water Don’t Mix
• Oil is nonpolar• Water is polar
“Like dissolves like”
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 470
Hydrogenation
Timberlake, Chemistry 7th Edition, page 570
+ H2
vegetable oils shortening stick margarine
tub (soft)margarine
heat, nickel catalyst
Molecular Polarity
H–C–H
H
H–C–H
H–C–H
H–C–H
H
H H
O
nonpolar molecules: -- e– are shared equally-- tend to be symmetric
e.g., fats and oils
polar molecules: -- e– NOT shared equallye.g., water
“Like dissolves likeLike dissolves like.”polar + polar = solutionnonpolar + nonpolar = solutionpolar + nonpolar = suspension (won’t mix evenly)
Using Solubility Principles
C=CCl
ClCl
Cl
Chemicals used by body obey solubility principles.
-- 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)-- (tetra) perchloroethylene is in common use
-- water-soluble vitamins: e.g., vit. C
Used,FilteredPerc
Perc Storage/Collection
Distiller
Pressing
Water Discharge
Air toAtmosphere
DirtyClothes
FinishedClothes
DirtyPerc
Perc
Warm VaporFrom Dryer
CondensedLiquid Perc
CleanPerc
CollectedUsedPerc
HazardousWaste* *Soil, dirt, unrecovered Perc
NewPerchloro-ethylene
(PERC)
Filter
Separator
Condenser
Dry Cleaning Unit-One unit washes and dries
Washing Process
Drying Process
Process used forWash and dry
MODEL OF A SOAP MOLECULE
NONPOLARHYDROCARBON
TAIL
POLARHEAD
Na1+
emulsifying agent (emulsifier): -- molecules w/both a polar AND a nonpolar end-- allows polar and nonpolar substances to mix
detergent lecithin eggse.g., soap