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OC Class 6. OB: Examining and Mastering the Organic Chemical Reactions: Substitution, Addition, Fermentation, Esterfication, Polymerization, and Saponification.
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OC Class 6 OB: Examining and Mastering the Organic Chemical Reactions: Substitution, Addition, Fermentation, Esterfication, Polymerization, and Saponification.
We have seen substitution reactions last week when we discussed the formation of halocarbons. We need to stick halogens (F, Cl, Br, or I) into a saturated hydrocarbon. Being saturated, there is NO ROOM for any new atoms, so we need to substitute in one halogen atom for a hydrogen atom. Substitution reactions: Saturated + Halogen Halocarbon + HX Hydrocarbon (alkane) + (F, Cl, Br, or I) (X = halogen atom) Propane + F2 1-fluoropropane + HF + F2 F + HF
Do these 2 substitution reactions… Ethane + chlorine yields… Butane + iodine yields 2-iodobutane + HI
Do these 2 substitution reactions… Ethane + chlorine yields chloroethane + HCl Butane + iodine yields 2-iodobutane + HI + Cl2 Cl + HCl + I2 + HI I
For ADDITION reactions, we’ll start with a halogen and a NON-SATURATED hydrocarbon, an alkene or alkyne. We will ADD the halogen into it Ethene + Bromine yields 1,2 di bromoethane + Br2 Br Br The double bond opens, a bromine is added to each carbon (not onto 1 carbon) A triple bond would open into a double bond, and you’d add the Br the same way.
Do these 2 addition reactions Propene and chlorine yields… Ethyne and fluorine yields….
Propene and chlorine yields 1,2 dichloropropane Ethyne and fluorine yields 1,2 difluoroethene • Cl Cl + Cl2 F F H—C=C—H + F2
Fermentation is a chemical process known to humans for thousands of years. It turns fruit juice, or vegetable juice into ethanol and carbon dioxide. It’s how to make champagne, or wine, or beer, or even stronger liquors. It’s a billions of dollars a year industry around the world, it’s wonderful in small amounts when you’re over 21, and it can be terrible too. Devastating. It’s not good for any one, your body must process this ethanol away as a toxin. It can change your life into hell if you drink too much of it. It will change the way you think, and it is not as casual as most teenagers think. Don’t drink until you’re 21. Never ever drive or go driving with someone who has been drinking. Ever, anyone, no matter what.
Fermentation is the organic chemical reaction that turns sugars into ethanol and carbon dioxide by way of yeast enzymes. This is not a reaction that happens outside of the yeast. Fish gotta swim, Yeast gotta live. Yeast excrete waste products called ethanol and CO2, by anerobicrespiration. yeast enzymes in water Sugars CH3CH2OH + CO2
Different fruit juices, or vegetable juices make for different kinds of alcoholic beverages. Some keep the carbon dioxide and are carbonated, some release the bubbles and are called “still” wines or liquors. Still referring to the lack of bubbles. White grapes make white wine, pink grapes make pink wine& red grapes make red wine. Potato juices will end up as vodka, rye will ferment into rye whiskey, and barley and hops will ferment into beer. Different processes will make the content of the ethanol higher or lower. When alcohol is 100 proof, that means that it should catch fire when lit. 100 proof = 50% ethanol by volume. Most wines are closer to 20 or 30 proof (10-15% ethanol). The only alcohol that is fermented to drink by humans is ethanol. Most of the “other” alcohols will kill you right out, and painfully. Do not drink before you are 21. Do not drink to excess ever. Never, ever drive when drinking, or when the driver is drinking. Most people in jail were drinking just before their crimes. (or taking drugs).Use your mind, do not be seduced by the allure of alcohol, it’s just not that cool. I am over 21 and I can do what ever I like, but I don’t drink much ever and I’m okay.
Polymerization the process of making plastics. At right is a clip from the movie “The Graduate” with Dustin Hoffmann (he’s the guy on the left). That other man is saying to Ben (who just graduated from college) “I have just oneword of advice for you.” “Are you listening to me Ben?” “Yes.“ Ben replies. So he says: “Plastics.”
Polymerization mer means unit or body -ization means the process of poly means many the organic chemical reaction of making plastics or polymers.
Triskaidekaphobia The fear of the number 13. Phobia means: a persistent, irrational fearof a specific object, activity, or situation (or number!) that leads to a compelling desire to avoid it.
A lot of… ethene molecules can form long chains of a polymer called polyethene catalyst n catalysts break open those double bonds, allowing the “mers” to unite into chains that go on and on, and are indefinite in length. There is not a “real” formula for the polymer formed. the polyethene formula is (-CH2CH2-)n
Other plastics that you probably know of already are PVC, or polyvinyl chloride, the white pipes made in Vestal, and used for plumbing in your home. It starts out with CH2=CHCl as the “mer”. You’d call this chloroethene. Polyethylene is what thin clear plastic food bags are made of (look at your sandwich bag). Polystyrene (Styrofoam) is another plastic you have used. This one is white and opaque. Different plastics, different properties. They all start with a “mer” and form polymers with unique properties. Teflon (used in frying pans) is Polytetrafluoroethylene. The “mer” is CF2=CF2 which you’d call 1,1,2,2 tetrafluroethene. (technically the 1,1,2,2 is unnecessary, there are no other places to put the 4 fluorine atoms) CH2=CCl2 is the mer that makes saran wraps (thin clear food plastic). you’d call this compound 1,1 dichloroethene.
Esterfication is when an acid and an alcohol form an ester (and water). When complete, deep breath in through the nose; smile. Acid + alcohol yields an ester + H2O we will combine propanoic acid + ethanol (draw this now)
Acid + alcohol yields an ester + H2O we will combine propanoic acid + ethanol H H + HO C C H OH H H Acids will ionize the hydrogen in the –COOH group. Alcohols do not ionize at all. To form water, something a bit odd happens. The OH in the -COOH group combines to the H in the -OH group of the alcohol to make the water HOH. The rest of the molecules squeeze into a big molecule, the ester.
Acid + alcohol yields an ester + H2O we will combine propanoic acid + ethanol H H + HO • C • C H OH H H This OH and H makes the water. the rest of the 2 molecules go together like this: + HOH Ethyl Propanoate
Draw the reactant molecules and product molecules (and product names) butanoic acid + 1-propanol form an ester + water
butanoic acid + 1-propanol form an ester + water H HH + HO C • C • C H OH • H HH + HOH PropylButanoate
I use that stuff SAPONIFICATION is the most complex reaction but the easiest to recognize and remember. If you misspell the reaction the first four letters might spell out SOAP. In fact, this organic reaction is the reaction that makes SOAP. (the take a bath kind) Did I say SOAP?
+ 3 NaOH You can use any 3 bases, different bases will result in different kinds of soap, softer, harder, liquid or solid, different colors, etc. Note, a fat like this contains 3 ester groups, this is a triple ester
The products of saponification are a triple alcohol (you have heard of glycerol, and soap. Note, the soap has a “triple” molecular shape, and contains an ION as well. This ion makes it better able to break up surface tension in water (remember those bugs?) We don’t have to name these molecules, just “recognize” them at the end of this equation.