Chapter 20 Organic Chemistry Objective: Students will understand how to name the alkanes.

EXITBOOKS! THOSE WHO CHECKED OUT A BOOK! TURN IN YOUR BOOK NEXT TIME Copyright © by McDougal Littell. All rights reserved.2

EXIT What is ORGANIC Chemistry? The study of carbon-containing compounds (typically chains of carbon atoms) and their properties. Carbon atoms can link to other carbon atoms indefinitely. Copyright © by McDougal Littell. All rights reserved.3

EXITHYDROCARBONS Compounds containing carbon and hydrogen only. There are several classes. The first is ALKANES. Copyright © by McDougal Littell. All rights reserved.4

EXITALKANES Alkanes are the simplest of the hydrocarbons. They only contain carbon-hydrogen bonds and carbon-carbon single bonds. The first ten are: Their formulas are always C x H 2x+2 C 6 H 14 is an example Copyright © by McDougal Littell. All rights reserved.5

EXIT TEN ALKANES Copyright © by McDougal Littell. All rights reserved.6 The names of the Alkanes always end in -ane

EXIT 7 Figure 20.2: The Lewis structure of ethane.

EXIT Name the Compound Copyright © by McDougal Littell. All rights reserved.8

EXIT What is a branched-chained alkane? Copyright © by McDougal Littell. All rights reserved.9

EXIT Naming Branched Chained Alkanes Page 641 of your text Copyright © by McDougal Littell. All rights reserved.10

EXIT Naming Branched Chained Alkanes Page 641 and 642 of your text Copyright © by McDougal Littell. All rights reserved.11

EXIT Naming Branched Chained Alkanes Page 643 of your text Copyright © by McDougal Littell. All rights reserved.12

EXIT Naming Branched Chained Alkanes Page 643 of your text Copyright © by McDougal Littell. All rights reserved.13

EXIT Name the Compound Copyright © by McDougal Littell. All rights reserved.14

EXIT Name The Compound Copyright © by McDougal Littell. All rights reserved.15

EXIT Calculating the molar-mass Branched Chained Alkanes Calculating the molar mass of alkanes is easy. 1. Determine the total number of carbons and times that number by Then determine the number of hydrogens. ( 2x the carbons + 2 more) 3. Add the two together. Copyright © by McDougal Littell. All rights reserved.16

EXIT Calculating the molar-mass Branched Chained Alkanes Example: Find the molar-mass of 2,3-dimethylpentane. There are 5 carbons in pentane and 1 carbon in each methyl so a total of 7. That means there are a total of 16 hydrogen atoms. 12 x = =

EXIT Isotopes of Butane Copyright © by McDougal Littell. All rights reserved.18

EXIT Stop here for the 1 st Assignment Copyright © by McDougal Littell. All rights reserved.19

EXIT Start here for the 2 nd Assignment Copyright © by McDougal Littell. All rights reserved.20 For this day we will draw and name the isomers of Heptane. Then we will learn how to identify and name ALKENES and ALKYNES There is a clicker quiz named “ALKENES AND ALKYNES”

EXITISOMERS Copyright © by McDougal Littell. All rights reserved.21

EXITISOMERS Copyright © by McDougal Littell. All rights reserved.22 In class assignment Draw and name the nine isomers of Heptane C 7 H 16

EXIT What is a BLEVE? An acronym for “boiling liquid escaping vapor explosion VIDEO #1 Video #2 The jet sound is a bleve! Video #2 Video #3 Notice how the fire keeps its shape? That’s because the fuel must mix with oxygen in just the right ratio Video #3 Copyright © by McDougal Littell. All rights reserved.23

EXIT A closer look at this fire Copyright © by McDougal Littell. All rights reserved.24

EXITPropane Copyright © by McDougal Littell. All rights reserved.25

EXIT Properties of ALKANES Copyright © by McDougal Littell. All rights reserved.26

EXITAlkenes Alkenes are hydrocarbons with double bonds. They are unsaturated and often referred to as “olefins” The name of alkenes end in –ene. Ethene, Propene Butene Pentene Copyright © by McDougal Littell. All rights reserved.27

EXIT Cis and Trans Double bonds on the carbons prevents the carbon atoms from rotating around each other. Copyright © by McDougal Littell. All rights reserved.28

EXIT Naming Alkenes When naming alkenes give the lowest number to the double bond. Then name the side chains Copyright © by McDougal Littell. All rights reserved.29

EXIT Name the compound Trans-3-heptene 4-methyl-cis-2 pentene Copyright © by McDougal Littell. All rights reserved.30

EXITButadiene Butadiene is butane with two double bonds C=C-C=C 2,3-butadiene Copyright © by McDougal Littell. All rights reserved.31

EXITCyclo-hydrocarbons Hydrocarbons that are in a ring are called cyclo-hydrocarbons Copyright © by McDougal Littell. All rights reserved.32

EXITAlkynes Alkynes are hydrocarbons that have a triple bond. They are very reactive. Video controlled explosion of ethyne. Copyright © by McDougal Littell. All rights reserved.33

EXIT Naming Aromatic Compounds BENZENE Objective: Students will understand the historical significance of Benzene, its structure and how to name compounds containing benzene. Copyright © by McDougal Littell. All rights reserved.34

EXIT Copyright © by McDougal Littell. All rights reserved.35 Figure 20.8: Two Lewis structures for the benzene ring.

EXIT1.3.5-Cyclohexatriene. Copyright © by McDougal Littell. All rights reserved.36

EXIT Early uses In the 19th and early-20th centuries, benzene was used as an after-shave lotion because of its pleasant smell. Prior to the 1920s, benzene was used as an industrial solvent. To decaffeinate coffee Later benzene was used to improve the anti- knock in gasoline. Copyright © by McDougal Littell. All rights reserved.37

EXIT Benzene is an AROMATIC Compound The term 'aromatic' was assigned before the physical mechanism determining aromaticity was discovered, and was derived from the fact that many of the compounds have a sweet scent. Copyright © by McDougal Littell. All rights reserved.38

EXITBenzene Copyright © by McDougal Littell. All rights reserved.39

EXIT Tylenol and Advil Copyright © by McDougal Littell. All rights reserved.40

EXITToluene When a methyl group is attached to a benzene ring, the whole structure is referred to as toluene. Copyright © by McDougal Littell. All rights reserved.41 This is the #1 Carbon

EXIT Naming Compounds Containing Toluene Copyright © by McDougal Littell. All rights reserved.42 toluene 2 chloro-toluene 2,3 dichloro-toluene

EXIT2,4,6-trinitrotoluene Copyright © by McDougal Littell. All rights reserved.43

EXIT Phenyl Groups Copyright © by McDougal Littell. All rights reserved.44

EXITPetroleum This is a mixture of many compounds taken out of the earth and separated into purer compounds by means of a distillation tower. Copyright © by McDougal Littell. All rights reserved.45

EXIT Copyright © by McDougal Littell. All rights reserved.46 Figure 20.7: Benzene C 6 H 6.

EXIT Copyright © by McDougal Littell. All rights reserved.47 Figure 20.8: Shorthand notation for benzene rings.

EXIT Copyright © by McDougal Littell. All rights reserved.48 Figure 20.10: Names of some common monosubstitut ed benzenes.

EXIT Copyright © by McDougal Littell. All rights reserved.49 Figure 20.5: Energy sources used in the United States.

EXIT Copyright © by McDougal Littell. All rights reserved.50 Figure 20.6: Ball-and-stick model of ethylene.

EXIT Copyright © by McDougal Littell. All rights reserved.51 Figure 20.13: Some carboxylic acids.

EXIT Copyright © by McDougal Littell. All rights reserved.52 Table 20.5

EXIT What is an Alcohol? Alcohols: Contain the hydroxyl functional group, –OH which replaces an –H in the alkane. Copyright © by McDougal Littell. All rights reserved.53

EXIT How to name Alcohols Alcohols are named by replacing the “-e” ending of the alkane with a “-ol” ending. methane, CH 4, gives methanol, CH 3 OH ethane, C 2 H 6, gives ethanol, C 2 H 5 OH Propane,, gives 2-propanol, Copyright © by McDougal Littell. All rights reserved.54

EXIT Organic Acids Organic Acids Contain the carboxyl Functional Group, –COOH Copyright © by McDougal Littell. All rights reserved.55

EXIT What is a Keytone? Ketones: Have the carbonyl functional group bonded between two hydrocarbon units. Copyright © by McDougal Littell. All rights reserved.56

EXIT Naming Keytones Ketones are named by replacing the -e ending of the alkane with the -one ending and prefixing the name with the number of the carbonyl carbon Copyright © by McDougal Littell. All rights reserved.57

EXITAldehydes Copyright © by McDougal Littell. All rights reserved.58

EXIT Copyright © by McDougal Littell. All rights reserved.59 Figure 20.9: The bonding in the benzene ring is a combination of different Lewis structures.