Chapter 11: Bonding and Molecular Structure: Carbon – More Than Just Another Element
Chapter 11 Problem Set
Pages 531-535
2, 3, 4, 5, 6, 7, 11, 12, 13
11.1 THE UNIQUENESS OF CARBON
Why is carbon so unique?
What is kinetic stability?
The Diversity of Bonds Formed by Carbon
Carbon forms four bonds:
4 single bonds
2 single and 1 double bond
2 double bonds
1 triple bond and 1 single bond
When carbon forms four single bonds, it has a tetrahedral structure.
When carbon atoms form a double bond, there is the possibility of forming cis and trans isomers.
The diversity of carbon is illustrated by the allotropes of carbon.
Stability of Carbon Compounds
The Importance of Bond Dissociation Energy (refer to Chap 9 sec 5)
The C-C bond energies are quite strong. Compare some carbon bond energies with those of silicon.
Kinetic Stability of Carbon Compounds
What is kinetic stability?
An example of kinetic stability is the fact that ethylene doesn't undergo spontaneous polymerization.
11.2 HYDROCARBONS
What are hydrocarbons?
Alkanes
What is the general formula for alkanes?
Alkanes, which have more than three carbon atoms, can form structural isomers.
For example, consider the two structural isomers for C4H10
Each alkane is a framework of tetrahedral carbon atoms, and each carbon atom must have four single bonds.
EXAMPLE 11.1 Page 489Drawing Structural Isomers of Alkanes
Draw structures of the five isomers of C6H14.Using Appendix E, name each of the structures.
EXERCISE 11.1 Page 487Drawing Structural Isomers of Alkanes
Draw and name the 9 isomers having the formula C7H16 Hint: one heptane, two hexanes, five pentanes, one butane
Cycloalkanes, CnH2n
Cyclohexane has two less hydrogen atoms that hexane.
The six carbon atoms in cyclohexane do not lie in a plane.
Properties of Alkanes
What are some common alkanes?
Small alkanes are gases
11.3 ALKENES AND ALKYNES
What is stereoisomerism?
One form of stereoisomerism is geometric isomerism.
EXERCISE 11.2 Page 495Drawing Structural Isomers of Alkenes From a Formula
There are 17 possible isomers with the formula C6H12.Draw structures for the five isomers in which the longest chain has six carbons.
Properties of Alkenes and Alkynes
Addition Reactions of Alkenes and Alkynes
EXERCISE 11.3 Page 497Reactions of Alkenes
- Draw the structure of the compound obtained from the reaction of HBr with ethylene
- Draw the structure for the compound that comes from the reaction of Br2 with cis—2-butene. Give a reasonable name for the structure.
What are unsaturated compounds?
Aromatic Compounds
Benzene is a key molecule in chemistry. A source of many aromatic compounds in coal tar
The Structure of Benzene
It is an unsaturated compound.
Substitution Reactions of Aromatic Compounds
It is possible to substitute a halogen atom, a nitro group, or an alkyl or other hydrocarbon group for one or more hydrogen atoms of benzene.
Difference between substitution and addition
EXERCISE 11.4 Page 500 Isomers of Substituted Benzenes
Draw a structure for the compound p-dichlorobenzene – one of the 2 aromatic compounds used in moth balls.
Properties of Aromatic Compounds
Benzene molecules have unusual stability that is associated with the unique pi bonding in molecules. The extra stability is termed resonance stabilization.
11.4 ALCOHOLS AND AMINES
What is a functional group?
Alcohols
What is an alcohol functional group?
What are some uses of methanol?
How is industrial ethanol made?
EXERCISE 11.5 Page 505 Structural Isomers of Alcohols
Draw the structures and name the 4 isomers with the formula C4H9OH. (two have framework of butane and two are derived from 2-methyl-propane.)
Properties of Alcohols
Account for the fact that methane is essentially insoluble in water, whereas methanol is completely miscible with water.
What is an ether?
Amines
What are primary, secondary, and tertiary amines?
Properties of Amines
The smallest amines are water-soluble.
All amines are bases.
11.5 COMPOUNDS WITH A CARBONYL GROUP
The C = O group is called the carbonyl group
aldehydes, ketones, and carboxylic acids are oxidation products of alcohols
The oxidation of primary alcohols yields an aldehyde
The oxidation of secondary alcohols yields a ketone
Aldehydes and Ketones
Aldehydes and ketones have pleasant odors and are often used as the basis for fragtances. For example benzaldehyde is responsible for odor in cherries and almonds SEE Table 11.9
EXERCISE 11.6Page 512Aldehydes and Ketones
Draw structural formulas for 2-pentanone. Draw structures for a ketone and two aldehydes that are isomers of 2-pentanone, and name each of these compounds.
EXERCISE 11.7 Page 512 Aldehydes and Ketones
Draw structures and name the aldehyde or ketone that is formed upon oxidation of the following alcohols: 1-butanol, 2-butanol, 2-methyl-1-propanol Are the 3 compounds isomers?
Carboxylic Acids (Organic Acids)
What is the most common organic acid?
What are some naturally occurring organic acids?
In an organic acid, what hydrogen atom is the acidic hydrogen?
Esters
What is esterification?
hydrolysis
EXERCISE 11.8 Page 516 Esters
Draw the structure and name the ester formed from each of the following reactions.
- propanoic acid and methanol
- butanoic acid and 1-butanol
- hexanoic acid and ethanol
Amides
What is a structural formula of an amide?
11.6 FATS AND OILS
Fats and Oils are triesters made from glycerol and long chain fatty acids.
A fatty acid may be unsaturated, monounsaturated, polyunsaturated
What is saponification? (soap making)
11.7 Synthetic Organic Polymers
Classifying Polymers
What is a polymer?
What is a monomer?
What is a thermoplastic?
What is a thermosetting plastic?
Addition Polymers
Polyethylene and Other Polyolefins
The equation for the production of polyethylene can be represented by the
Equation nH2C = CH2 (-CH2CH2-)n
What is the difference between high density polyethylene and low density
polyethylene?
Polymers formed from substituted ethylenes have a range of properties and uses….
Natural and Synthetic Rubber
Rubber is a naturally occurring polymer whose monomers are
2-methyl-1,3-butadiene (isoprene).
What are elastomers?
What are copolymers?
Condensation Polymers
What is a condensation reaction?
Polyesters
Consider the formation of polyethylene terephthalate…
Polyamides
What is Nylon-6,6?
New Polymer Materials
What are composites?
Proteins, Natural Polymers
What is a peptide bond?
What are polypeptides?
What is a primary structure of a protein?
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