1. Chapter 22
Carbon & Hydrocarbons

2. Chapter 22 Vocabulary Diamond Graphite Fullerenes
Delocalized electrons
Organic compounds
Catenation
Hydrocarbons
Isomers
Structural formula
Structural isomers
Geometric isomers
Saturated hydrocarbon
Alkanes
Cycloalkanes
Alkyl groups
Natural gas
Petroleum
Unsaturated hydrocarbons
Alkynes
Aromatic hydrocarbons
benzene

3. Chapter 22 Vocabulary
Diamond is a colorless, crystalline, solid form of carbon
Graphite is a soft, black, crystalline form of carbon that is a fair conductor of electricity
Fullerenes are dark colored solids made of spherically networked carbon atom cages.
Delocalized electrons are electrons shared by more than two atoms
Organic compounds covalently bonded compounds containing carbon, excluding carbonates and oxides.
Catenation the covalent bonding of an element to itself to form chains or rings.
Hydrocarbons are composed of only carbon and hydrogen; they are the simplest organic compounds.
Compounds that have the same molecular formula but different structures are called isomers.
Structural formula indicates the number and types of atoms present in a molecule and also shows the bonding arrangement of the atoms.

4. Chapter 22 Vocabulary
Structural isomers are isomers in which the atoms are bonded together in different orders.
Geometric isomers are isomers in which the order of atom bonding is the same but the arrangement of atoms in space is different.
Saturated hydrocarbons are hydrocarbons in which each carbon atom in the molecule forms four single covalent bonds with other atoms.
Hydrocarbons that contain only single bonds are alkanes.
Cycloalkanes are alkanes in which the carbon atoms are arranged in a ring, or cyclic, structure.
Alkyl groups are groups of atoms that are formed when one hydrogen atom is removed from an alkane molecule
Natural gas is a fossil fuel composed primarily of alkanes containing one to four carbon atoms
Petroleum is a complex mixture of different hydrocarbons that varies greatly in composition.
Unsaturated hydrocarbons are hydrocarbons in which not all carbon atoms have four single covalent bonds.

5. Chapter 22 Vocabulary
Structural isomers are isomers in which the atoms are bonded together in different orders.
Geometric isomers are isomers in which the order of atom bonding is the same but the arrangement of atoms in space is different.
Alkenes are hydrocarbons that contain double covalent bonds.
Hydrocarbons with triple covalent bonds are alkynes.
Aromatic hydrocarbons are hydrocarbons with six membered carbon rings and delocalized electrons
Benzene is the primary aromatic hydrocarbon

6. Alkanes and Aromatic Hydrocarbons
Organic Compounds
Bonding in Hydrocarbons
Naming Alkanes
Properties of Alkanes

7. Organic Chemistry and Hydrocarbons
_________ originally meant chemicals that came from ______________.
1828 German chemist Friedrich Wohler synthesized urea in a lab
Today, organic chemistry is the chemistry of virtually all compounds containing the element ___________.

8. Friedrich Wohler
1800 – 1882
Used inorganic substances to synthesize urea, a carbon compound found in urine.
This re-defined organic chemistry.

9. Organic Chemistry and Hydrocarbons
Over a million organic compounds, with numerous properties
Why so many? Carbon’s unique bonding ability!
Let’s start with the simplest of the organic compounds: Hydrocarbons

10. Organic Compounds Contain _________________ Have ______________ bonds
Have low _____________ points
Have low _______________ points
Burn in air (oxygen)
Are soluble in _____________ solvents
Form large ________________

11. Alkanes Contain ______ and _________ only
Contain ____________ bonds C-C
Have _____ bonds to every carbon (C) atom
Are ________________

12. Alkanes Structural Formulas Show the bonds between each of the atoms
H H
 
H  C  H H C H
CH4 - methane
In methane, CH4 the four valence electrons of carbon are shared with the single electrons of four hydrogen (H) atoms. Each pair of electrons is a single bond, which can be drawn as a line. When a structure is drawn to show each bond, it is called a complete structural formula.

13. Alkanes Structural Formulas H H Condensed Structural Formulas
H C C H CH3 CH3
H H Ethane
H H H
H C C C H CH3 CH2 CH3
H H H Propane
The complete structural formula for ethane shows the single bonds between two carbon atoms and six H atoms. The complete structural formula of propane shows the 3-carbon chain with single bonds to the attached H atoms. To write a condensed structural formula, the H atoms are written as a group next to their respective C atoms.

14. Alkanes Structural Formulas Structural Formula H H H H C C C H H H H
CH3 CH2 CH3
CH3CH2CH3
Structural Formula
The complete structural formula for ethane shows the single bonds between two carbon atoms and six H atoms. The complete structural formula of propane shows the 3-carbon chain with single bonds to the attached H atoms. To write a condensed structural formula, the H atoms are written as a group next to their respective C atoms.
Condensed Structural Formula
Condensed Formula

15. Alkanes Structural Formulas Examples: _____________ formula
Condensed__________________

16. Alkanes

17. Organic Naming Prefixes

18. Naming Alkanes ____ane 1 CH4 ____ane 2 CH3CH3 ____ane 3 CH3CH2CH3
Name # carbons Structural Formula
____ane 1 CH4
____ane 2 CH3CH3
____ane 3 CH3CH2CH3
____ane 4 CH3CH2CH2CH3
____ane 5 CH3CH2CH2CH2CH3
The names of organic compounds are determined by the IUPAC rules (International Union of Pure and Applied Chemistry). The stem of the name states the number of carbon atoms in the carbon chain of the compounds. The suffix, in this case –ane, indicates the alkane family.

19. Naming Alkanes ___ane 6 CH3CH2CH2CH2CH2CH3
Name # carbons Structural Formula
___ane CH3CH2CH2CH2CH2CH3
____ane CH3CH2CH2CH2CH2CH2CH3
___ane CH3CH2CH2CH2CH2CH2CH2CH3
___ane CH3 CH2 CH2CH2CH2CH2CH2CH2CH3
___ane 10 CH3CH2CH2CH2CH2CH2CH2CH2CH2CH3

20. Practice Problems A. What is the condensed formula for H H H H
H C C C C H
H H H H
B. What is its molecular formula?
C. What is its name?

21. Reactions of Alkanes Combustion In the Cell
alkane + O CO2 + H2O + heat
Combustion In the Cell
Metabolic oxidation is combustion
C6H12 O6 + 6O CO2 + 6H2O + heat
glucose

22. Combustion Example Complete the combustion reaction for C3H8 + O2 +
Balance your equation

23. Practice Problem
Complete and balance the reaction for the complete combustion of C7H16

24. Alkanes and Aromatic Hydrocarbons
Branched Alkanes
Structural Formulas

25. Alkyl Groups Branches on carbon chains H H C CH3 _________ H H
H C C CH3CH2 _________
An alkyl group is composed of one or more carbon atoms attached to a carbon chain. An alkyl group is derived from an alkane by removing one hydrogen. The ending –ane of the alkane is changed to –yl. The carbon branch from methane is the methyl group. The carbon branch from ethane is the ethyl group.

26. Alkyl Groups

27. Branched Alkanes CH3 CH3CHCH3 methyl groups CH3 CH3 CH3CHCH2CHCH3
In the structural formula of an alkane, the alkyl group is typically attached vertically above or below the carbon chain.

28. Naming Branched Alkanes
CH methyl branch
CH3CH2CH2CHCH2CH3
Count
A branched-chain alkane is named by indicating the attached groups on the longest carbon chain. In this example, the longest carbon chain has 6 carbon atoms.

29. Naming Branched Alkanes
CH methyl branch
CH3CH2CH2CHCH2CH3
Count
3-Methylhexane
on third C CH six carbon chain
group
The chain is numbered to give the side group or methyl group a location on carbon 3 in the chain.

30. Naming Alkanes

31. Naming Alkanes Example

32. Naming Practice Problems
A CH CH3
CH3CHCH2CHCH3
B CH CH3
CH3CH2CHCH2CCH2CH3
CH3

33. Practice Problems Write a condensed structure for
A. 3,4-dimethylheptane
B. 2,2-dimethyloctane

34. Isomers Same _____________ formula Same ________ and ______ of atoms
Different ________________ of atoms
Also have different properties, such as b.p., m.p., and reactivity
Structural isomers are compounds that have the same molecular formula with different arrangements of the atoms.

35. Structural Isomers ___________________ are isomers in which
the atoms are bonded together in different orders.

36. Geometric Isomers
____________________ are isomers in which the order of atom bonding is the same but the arrangement of atoms in space is different.

37. Examples of Isomers CH3 The formula C4H10 has two different structures
CH3CH2CH2CH3 CH3CHCH3
Butane methylpropane
When a CH3 is is used to form a branch, it makes a new isomer of C4H10.

38. Practice Problem
Write 3 isomers of C5H12 and name each.

39. Practice Problems
Write the structural formulas of 3 isomers that have the formula C5H12. Name each.

40. Alkanes and Aromatic Hydrocarbons
Cycloalkanes
Aromatic Hydrocarbons

41. Cycloalkanes _____________ CH2 CH2 CH2 _____________ CH2 CH2 CH2 CH2
The is a group of alkanes that have a cyclic structure. These cycloalkanes contain a carbon chain that is in a ring. Each cycloalkane has a formula that is 2C less than the corresponding alkane. For example, propane is C3H8 whereas cyclopropane ic C3H6. Butane is C4H10 and cyclobutane is C4H10. The names of the cyclic structures use the prefix cyclo in from of the alkane name for the carbon chain.

42. More Cycloalkanes
____________ CH2
CH CH2
CH CH2
____________
CH2

43. Naming Cycloalkanes with Side Groups
Number of Naming
side groups
One Side group name goes in front of the cycloalkane name.
Two or more Number the ring in the direction that gives the lowest numbers to the side groups.

44. Cycloalkanes with Side Groups

45. Practice Problems

46. Aromatic Compounds and Benzene
___________________ contain __________.
Benzene, C6H6 , is represented as a ______ carbon ring with _____ double bonds.
Two possible can be drawn to show benzene in this form.

47. Benzene Structure
The structures for ______________ can also be written as a single structure where the alternating double bonds are written as a circle within the ring.
Benzene
structure

48. Aromatic Compounds in Nature and Health
Many aromatic compounds are common in _____________ and in _____________.

49. Naming Aromatic Compounds
Aromatic compounds are named with benzene as the parent chain. One side group is named in front of the name benzene.
methylbenzene chlorobenzene
(toluene)

50. Naming Aromatic Compounds
When two groups are attached to benzene, the ring is numbered to give the lower numbers to the side groups. The prefixes ortho (1,2), meta (1,3-) and para (1,4-) are also used.

51. Some Common Names
Some substituted benzene rings also use a common name. Then naming with additional more side groups uses the ortho-, meta-, para- system.

52. Practice Problems
Write the structural formulas for each of the following:
A. 1,3-dichlorobenzene
B. Ortho-chlorotoluene

53. Practice Problems Select the names for each structure:
1. Chlorocyclohexane
2. Chlorobenzene
3. 1-chlorobenzene
1. Meta-methyltoluene
2. Meta-dimethylbenzene
3. 1,3-dimethylbenzene

54. Haloalkanes, Alkenes, and Alkynes

55. Saturated and Unsaturated Compounds
Saturated compounds (alkanes) have the maximum number of hydrogen atoms attached to each carbon atom
Unsaturated compounds have fewer hydrogen atoms attached to the carbon chain than alkanes
Unsaturated compounds contain double or triple bonds alkenes & alkynes

56. Alkenes Carbon-carbon _____________ bonds Names end in -___________
H2C=CH2 ethene (ethylene)
H2C=CH-CH3 propene (propylene)
cyclohexene

57. Alkenes

58. Alkynes Carbon-carbon __________ bonds Names end in -_________
HCCH ethyne(acetylene)
HCC-CH3 propyne

59. Naming Alkenes and Alkynes
When the carbon chain has 4 or more C atoms, number the chain to give the lowest number to the double or triple bond.
CH2=CHCH2CH3 1-butene
CH3CH=CHCH3 2-butene
CH3CHCHCH3 2-butyne

60. Naming Alkenes
Slide 35

61. Naming Alkenes

62. Naming Alkynes
Slide 35

63. Practice Problem
Write the names for each of the following unsaturated compounds:
A. CH3CH2CCCH3
CH3
B. CH3C=CHCH3 C.

64. Hydrogenation
Adds a hydrogen atom to each carbon atom of a double bond
H H H H Ni
H–C=C–H + H H–C–C–H
H H
ethene ethane

65. Products of Hydrogenation
Adding H2 to vegetable oils produces compounds with higher melting points
Margarines
Soft margarines
Shortenings (solid)

66. Trans Fats
In the US, it is estimated that 2-4% of our total Calories is in the form of trans fatty acid.
trans fatty acids behave like saturated fatty acids in the body.
Several studies reported that trans fatty acids raise LDL-cholesterol. Some studies also report that trans fatty acid lower HDL-cholesterol
The trans fatty acids controversy will continue to be debated.

67. Unsaturated Fatty Acids
Fatty acids in vegetable oils are omega-6 acids (the first double bond occurs at carbon 6 counting from the methyl group)
A common omega-6 acid is linoleic acid
CH3CH2CH2CH2CH2CH=CHCH2CH=CH(CH2)7COOH 6
linoleic acid, a fatty acid

68. Trans Fats
In vegetable oils, the unsaturated fats usually contain cis double bonds.
During hydrogenation, some cis double bonds are converted to trans double bonds (more stable) causing a change in the fatty acid structure
If a label states “partially” or “fully hydrogenated”, the fats contain trans fatty acids.

69. Fats and Atheroschlerosis
Inuit people of Alaska have a high fat diet and high blood cholesterol levels, but a very low occurrence of atherosclerosis and heart attacks.
Fat in the Intuit diet was primarily from fish such as salmon, tuna and herring rather than from land animals (as in the American diet).

70. Omega-3 Fatty Acids
Fatty acids in the fish oils are mostly the omega-3 type (first double bond occurs at the third carbon counting from the methyl group).
linolenic acid 18 carbon atoms
CH3CH2CH=CHCH2CH=CHCH2CH=CH(CH2)7COOH 
eicosapentaenoic acid (EPA) 20 carbon atoms CH3CH2(CH=CHCH2)5(CH2)2COOH

71. Atherosclerosis
Plaques of cholesterol adhere to the walls of the blood vessels
Blood pressure rises as blood squeezes through smaller blood vessels
Blood clots may form
Omega-3 fatty acids decrease the “sticking” of blood platelets (fewer blood clots)
Omega-3 fatty acids can increase bleeding time

72. Questions (1) Ture or (2) False
A. ____ There are more unsaturated fats in vegetable oils.
B. ____ Vegetable oils have more omega-3 oils than found in fish.
C. ____ Hydrogenation of oils converts some cis-double bonds to trans- double bonds.
D. ____ Animal fats have more saturated fats.

73. Natural Gas Fossil fuels provide much of the world’s energy
Natural gas and petroleum contain mostly the aliphatic (or straight-chain) hydrocarbons – formed from marine life buried in sediment of the oceans
Natural gas is an important source of alkanes of low molecular mass

74. Natural Gas Natural gas is typically:
80% methane, 10% ethane, 4% propane, and 2% butane with the remainder being nitrogen and higher molar mass hydrocarbons
also contains a small amount of He, and is one of it’s major sources

75. Natural Gas
Natural gas is prized for combustion, because with adequate oxygen, it burns with a hot, clean blue flame:
CH4 + 2O2  CO2 + 2H2O + heat
Incomplete burning has a yellow flame, due to glowing carbon parts, as well as making carbon monoxide

76. Petroleum
The compounds found in petroleum (or crude oil) are more complex than those in natural gas
Usually straight-chain and branched-chain alkanes, with some aromatic compounds also
Crude oil must be refined (separated) before being used

77. Petroleum
It is separated by distillation into fractions, according to boiling pt.
Fractions containing higher molar mass can be “cracked” into more useful shorter chain components, such as gasoline and kerosene
involves catalyst and heat
starts materials for plastics and paints

78. Citations http://www.karentimberlake.com/