Chapter 19 Page 743

Game Plan Day 1: Lesson 1 Hydrocarbons….Make “booklet” Day 2: Lesson 2: Functional Groups Lab: Esters Day 3: Practice naming alkanes, alkenes, alkynes. Day 4: Lesson 3: More functional groups Day 5: Lesson 4: Polymers Day 6: Lab: Polymers Day 7: Test on Organic chemistry

Booklet: Organic Chemistry Front Page: Organic Chemistry Your name Pages 1: Types of Formulas and Prefixes Page 2: Alkane Pages 3-4: Alkene Pages 5-6: Alkyne Page 7: Aromatic Compounds

Organic chemistry: Front cover This is the study of the structures, properties, and reactions of organic compounds. These compounds contain carbon atoms and usually N, O, H, and S. There are millions of organic compounds….each carbon atom can bind with other carbon atoms to form long chains…these chains can have branches and ring structures.

Day 1: Lesson 1: Hydrocarbons Organic compounds are those that contain carbon atoms (except not carbon oxides, carbides, cyanides, or carbonates). The carbon atoms in organic compounds are covalently bonded to each other and other atoms… usually these other atoms are Hydrogen Nitrogen Oxygen Sulfur.

Formulas: page 1 1) molecular formula…just gives # and kind of atoms. For example: C2H6 2) Structural formula…is a model that uses element symbols and bond lines to represent a molecule. For example: H H │ │ H — C— C—H │ │ H H

Prefixes: Page 2 These prefixes tell you how many carbons are in the hydrocarbon. There are different endings …. 1 = meth6 = hex 2 = eth7 = hept 3 = prop8 = oct 4 = but9 = non 5 = pent10 = dec

Alkanes : page 3 The simplest hydrocarbons are alkanes. In alkanes, the carbon atoms are bonded to each other with single bonds. Alkanes can be straight chains, chains, with branches, or even rings. These prefixes tell you how many carbons are in the hydrocarbon. For an alkane, the ending is “ane” 1 = meth6 = hex 2 = eth7 = hept 3 = prop8 = oct 4 = but9 = non 5 = pent10 = dec

Alkanes continued: page 4 To write the formula for a simple alkane… C n H 2n +2 Where “n” is the number of carbon atoms. *Write the name, molecular formula, structural formula, and drawing of actual model for: pentane octane methane

Alkane practice: pages 3 and 4 Build, draw the structure, give the name, and formula for simple alkanes with 1-10 carbon atoms. 1 carbon6 carbons 2 carbons7 carbons 3 carbons8 carbons 4 carbons9 carbons 5 carbons10 carbons

Alkenes: page 5 The next simplest hydrocarbons are alkenes. In alkenes, the carbon atoms are bonded to each other with at least one double bond. The ending for an alkene is “ene. 6 = hex 2 = eth7 = hept 3 = prop8 = oct 4 = but9 = non 5 = pent10 = dec

Alkenes continued page 6 To write the formula for a simple alkene… C n H 2n Where “n” is the number of carbon atoms. *Give name, molecular formula, structural formula, and actual drawing of model for: 2-pentene 3-octene 3-heptene

Alkynes:page 7 The next group of hydrocarbons are alkynes. In alkenes, the carbon atoms are bonded to each other with at least one triple bond. The ending for an alkyne is “yne. 6 = hex 2 = eth7 = hept 3 = prop8 = oct 4 = but9 = non 5 = pent10 = dec

Alkyne: page 8 To write the formula for a simple alkyne… C n H 2n-2 Where “n” is the number of carbon atoms. *Give the name, the molecular and structural formula s, and draw the model for: 2-pentyne 3-octyne 2-heptyne

Aromatic Compounds: page 9 The last type of hydrocarbons are aromatic compounds. The smallest compound in this group is benzene, C 6 H 6. Benzene is a single ring. All aromatic compounds contain at least one benzene ring.

The word “aromatic” comes from the fact that these compounds were first found in sweet-smelling oils from spices and fruits. Naphthalene ( used in mothballs) contains an aromatic ring structure.

Cycloalkanes: page 10 Saturated: having on single bonds between carbon Unsaturated: have one or more double or triple bond between carbon atoms….or having a ring structure. Alkanes form rings when the carbon atoms at each end of a chain bond together. These alkanes are called cycloalkanes. Build, draw and name C5 H10…which is a ring structure.

Building molecular models Directions: Give name, molecular formula, structural formula, and actual drawing of model for: Alkanes pentane octane Methane Alkenes 2-pentene 3-octene 3-heptene Alkynes 2-pentyne 3-octyne 2-heptyne

Quiz: may use little book 1) Write the molecular formula for octane 2) Draw the structural formula for 2-hexene 3) Give the name for C 3 H 8 4) Is C 3 H 8 an alkane, alkene, or alkyne? How do you know? 5) Draw the structural formula for cyclobutane. 6) Write the molecular formula for butyne 7) Give the name for C 4 H 8 (no branches) 8) Is C 4 H 8 an alkane, alkene, or alkyne? How do you know? 9) Draw benzene…include hydrogens and double bonds. 10) Write the molecular formula for octene.

Isomers and Nomenclature

Isomers : Some alkanes contain one or more branches off the main chain of carbon atoms. A branched alkane has the same molecular formula as a straight-chain alkane. Compounds that have the same molecular formula, but different structural formulas, are isomers. Example: pentane C5 H12 “Chemistry: Packard, Jacobs and Marshall. Pearson /AGS Globe

Hexane Draw/name as the 5 different isomers for C 6 H 14

Solution for isomers for hexane C 6 H 14 (5 isomers) Hexane 2-Methylpentane 3-Methylpentane 2,2-Dimethylbutane 2,3-Dimethylbutane

Nomenclature: Notes on naming stuff: 1)When naming branches use these prefixes: one carbon branch = methyl group -CH3 two carbons branch = ethyl group -CH2CH3 three carbons branch = propyl group -CH2CH2CH3 2)Choose longest chain as your backbone…longest chain must include any double/triple bonds. 3)Number so you use the smallest numbers to locate branches. Then put branches in alphabetical order.

Practice: 2,3 -dimethyl heptane 3 -ethyl octane 5- propyl decane

Functional Groups Many hydrocarbons can react with other compound to produce a variety of new organic compounds. Example: CH4 + Cl2  CHCl3…….CH2Cl2…………CCl4 (chloroform) (Freon) (carbon tetrachloride) When one or more hydrogen atoms are replaced with a different atom or group of atoms, the result is a substituted hydrocarbon. These atoms and groups of atoms that can replace hydrogen are called functional groups.

Alkyl halides These compounds have a hydrogen replaced with a halogen…F, Cl, Br, or I General Formula: R – X where X = F, Cl, Br, or I where R represents the hydrocarbon part of the molecule. Carbon Tetrachloride, Freon (C Cl2F2), and chloroform (CHCl3) are all alkyl halides.

Alcohols These compounds contain the functional group –OH, which is called a hydroxyl group. General formula: R-OH Alcohols with less than 5 carbons are water soluble (because the molecule is polar). Isopropanol is rubbing alcohol. C3H7OH

Carboxylic Acids Carboxylic acids are substituted hydrocarbons that contain a carboxyl group -COOH. These are at the end of the molecule. General Formula: RCOOH Vinegar (acetic acid) is a carboxylic acid. HC2H3O2

Esters When an alcohol and a carboxylic acid react, a water molecule and an ester form. The functional group is -COOR General formula: R-COOR Most esters have a strong but pleasant odor…like wintergreen and many fruit flavorings. Isopentyl acetate C7H14O2

Ethers Ethers contain two hydrocarbon chains connected to an oxygen atom. Their functional group is the connecting O atom. General Structure is R-O-R’ Ethers are usually volatile (evaporates easily) and flammable (burns easily). Diethyl ether was used as an anesthetic for many years.

Ester Lab Procedure: Make a boiling water bath. To a regular test tube, use a pipet (or dropper) to add the amount of alcohol and carboxylic acid (you will mass out 1.0 grams salicylic acid because it is a solid). Use a stirring rod to mix or dissolve the chemicals. Add H 2 SO 4 dropwise, stirring after each drop to mix chemicals. A small amount of color change may occur. Using a test tube holder, place the test tube in a hot water bath (70 o C < temp < 100 o C ) for 4-5 minutes. Don’t let the water boil! Let the test tube cool a few minutes. Waft the vapors towards your nose and describe the odor.

Alcohol R 1 OHCarboxylic Acid R 2 COOH Sulfuric Acid H 2 SO 4 Ester R 2 COOR 1 Odor detected #11.0 ml ethanol1.0 ml n-butyric acid3 dropsEthyl n-butyrate #21.0 ml methanol1.0 grams salicylic acid 3 dropsMethyl salicylate #32.0 ml 1-pentanol1.0 ml acetic acid5 dropsn-pentyl acetate

Caution: Concentrated sulfuric acid (H 2 SO 4 ) is very dangerous! It will burn skin rapidly. CH 3 COOH (acetic acid) and CH 3 CH 2 CH 2 COOH (butyric acid) are highly corrosive to skin. They also smell really bad so these chemicals will be under the hood