Topics for Today

1
Topics for Today

• What is in my gasoline?
• Burning a gallon of gasoline

2
Readings for Today

• 3.6 Quantitative Concepts Mass
• 3.7 Quantitative Concepts Molecules and Moles

3
Topics for Wednesday

• Burning a gallon of gasoline.
• Where does my gasoline come from?

4
Readings for Wednesday

• 3.6 Quantitative Concepts Mass
• 3.7 Quantitative Concepts Molecules and Moles

5
Topics for Friday

• Exam 2

6
Topics for Monday

• Greenhouse Earth!

7
Topics for Today

• What is in my gasoline?
• Burning a gallon of gasoline

8
What is in my gasoline?
9
Gasoline
A volatile mixture of flammable liquid
hydrocarbons derived chiefly from crude petroleum
and used principally as a fuel for
internal-combustion engines.
10
Gasoline
A volatile mixture of flammable liquid
hydrocarbons derived chiefly from crude petroleum
and used principally as a fuel for
internal-combustion engines.
What is volatile?
11

• N2 O2 2NO
• NO O2 .OH VOCs NO2 VOCs

high temp
Easily goes into the vapor phase
VOC Volatile Organic Compounds
Contains C
12
Some VOCs
Methane (1 carbon) Ethane (2 carbons) Propane (3
carbons) Butane (4 carbons) Octane (8 carbons)
13
Gasoline
A volatile mixture of flammable liquid
hydrocarbons derived chiefly from crude petroleum
and used principally as a fuel for
internal-combustion engines.
What is volatile?
Vapor
Liquid
A barrel
14
Gasoline
A volatile mixture of flammable liquid
hydrocarbons derived chiefly from crude petroleum
and used principally as a fuel for
internal-combustion engines.
What is a mixture?
15
Matter
Is gasoline heterogeneous or homogenous?
Mixtures
Pure Substances
Compounds
Heterogeneous
Homogeneous
16
Gasoline
A volatile mixture of flammable liquid
hydrocarbons derived chiefly from crude petroleum
and used principally as a fuel for
internal-combustion engines.
What is flammable?
17

• Complete combustion of methane

CH4 2O2 ? CO2 2H2O
Undergoes combustion!
18
Gasoline
A volatile mixture of flammable liquid
hydrocarbons derived chiefly from crude petroleum
and used principally as a fuel for
internal-combustion engines.
What is a hydrocarbon?
19
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C
-C-H
H-C
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
Paraffin is a hydrocarbon
20
Gasoline
A volatile mixture of flammable liquid
hydrocarbons derived chiefly from crude petroleum
and used principally as a fuel for
internal-combustion engines.
A molecule that contains ONLY carbon and hydrogen
atoms.
What is a hydrocarbon?
21
Some hydrocarbons
Methane Ethane Propane Butane Octane
22
Some hydrocarbons
Methane Ethane Propane Butane Octane
23
Gasoline
A volatile mixture of flammable liquid
hydrocarbons derived chiefly from crude petroleum
and used principally as a fuel for
internal-combustion engines.
Gasoline is a mixture (homogeneous) of over 300
different compounds!!
24
Whats in my gasoline?
n-alkanes (straight chain)
Aromatics
15-25
iso-alkanes (branched)
20-30
15-25
lt1
20-30
Alkenes and Alkynes
Cycloalkanes
25
Whats in my gasoline?
n-alkanes (straight chain)
Aromatics
15-25
iso-alkanes (branched)
20-30
15-25
lt1
20-30
Alkenes and Alkynes
Cycloalkanes
26
n-alkanes in gasoline
n-pentane (5 carbons) n-hexane (6
carbons) n-heptane (7 carbons) n-octane (8
carbons) etc
The n stands for normal, or straight chain.
27
n-butane
H
H
H
H
C
H
C
H
C
C
H
H
H
H
n-butane, C4H10
28
n-butane
OR
H
H
H
H
C
H
C
H
C
C
H
H
H
H
n-butane, C4H10
29
Condensed structural formula!
CH3-CH2-CH2-CH3
n-butane, C4H10
30
n-butane
Figure 10.3 page 436
31
n-pentane
Be able to draw and name these structures from
methane to octane!
H
H
H
H
H
C
H
C
C
H
C
C
H
H
H
H
H
n-pentane, C5H12
32
Whats in my gasoline?
n-alkanes (straight chain)
Aromatics
15-25
iso-alkanes (branched)
20-30
15-25
lt1
20-30
Alkenes and Alkynes
Cycloalkanes
33
Compare
CH3-CH2-CH2-CH3
n-butane, C4H10
34
Compare
H
H
H
H
C
H
C
H
C
C
H
H
H
H
n-butane, C4H10
35
isobutane
Structural Formula
H
H
C
H
H
H
C
H
C
H
C
H
H
H
isobutane, C4H10
36
Condensed structural formula!
CH3
CH3-CH-CH3
isobutane, C4H10
37
n-butane
Figure 10.3 page 436
38
iso-butane
Figure 10.3 page 436
39

• n-butane and isobutane are isomers!
• Isomer Same chemical formula but different
  chemical structure!!!

40
isobutane
Also known as
H
H
C
H
H
H
C
H
C
H
C
H
H
H
isobutane, C4H10
41
isobutane
Also known as
H
2-methylpropane
H
C
H
H
H
C
H
C
H
C
H
H
H
isobutane, C4H10
42
isobutane
Also known as
H
2-methylpropane
H
C
H
H
H
C
H
C
H
C
1
2
3
H
H
H
isobutane, C4H10
43
isobutane
Also known as
methyl, .CH3
H
2-methylpropane
H
C
H
H
H
C
H
C
H
C
1
2
3
H
H
H
isobutane, C4H10
44
Some VOCs
Methane (1 carbon) Ethane (2 carbons) Propane (3
carbons) Butane (4 carbons) Octane ( 8 carbons)
45
Methyl (1 carbon) .CH3 Ethyl (2 carbons) Propyl
(3 carbons)
46
n-octane
Not too much of this in gasoline
CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH3
Chemical formula?
C8H18
47
isooctane
Isomers!!
CH3
CH3
CH3-C-CH2-CH-CH3
CH3
Chemical formula?
C8H18
48
2-methylpentane
CH3
CH3
CH
CH2
CH2
CH3
Chemical formula?
49
2-methylpentane
CH3
CH3
CH
CH2
CH2
CH3
Chemical formula?
C6H14
50
2-methylpentane
Same or different?
CH3
CH3
CH
CH2
CH2
CH3
?
CH3
CH
CH2
CH2
CH3
CH3
51
2-methylpentane
Same or different?
CH3
CH3
CH
CH2
CH2
CH3

CH3
CH
CH2
CH2
CH3
CH3
52
2-methylpentane
Same or different?
CH3
CH3
CH
CH2
CH2
CH3
1
2
3
4
5
?
CH3
CH3
CH2
CH2
CH
CH3
5
4
3
2
1
53
2-methylpentane
Same or different?
CH3
CH3
CH
CH2
CH2
CH3
1
2
3
4
5

CH3
CH3
CH2
CH2
CH
CH3
5
4
3
2
1
54
Whats in my gasoline?
n-alkanes (straight chain)
Aromatics
15-25
iso-alkanes (branched)
20-30
15-25
lt1
20-30
Alkenes and Alkynes
Cycloalkanes
55
cycloalkanes
cyclopentane methylcyclopentane cyclohexane methyl
cyclohexane etc
56
Basically geometrical figures
57
cyclopentane
CH2
H2C
CH2
CH2
H2C
Chemical formula?
C5H10
58
cyclopentane
Isomer of n-pentane?
CH2
H2C
CH2
CH2
H2C
Chemical formula?
C5H10
59
NO!! Different chemical formulas.
CH2
H2C
CH2
H
H
H
H
H
CH2
H2C
C
H
C
C
H
C
C
Cyclopentane, C5H10
H
H
H
H
H
Pentane, C5H12
60
cyclohexane
Isomer of n-hexane?
NO! I will leave you to prove this to yourself
H2C
CH2
H2C
CH2
H2C
CH2
Chemical formula?
C6H12
61
cyclohexane
H
H
H
H
C
C
H
H
C
C
H
H
C
C
H
H
H
H
62
methylcyclohexane
H
H
H
CH3
C
C
H
H
C
C
H
H
C
C
H
H
H
H
63
Whats in my gasoline?
n-alkanes (straight chain)
Aromatics
15-25
iso-alkanes (branched)
20-30
15-25
lt1
20-30
Alkenes and Alkynes
Cycloalkanes
64
Alkenes

• Hydrocarbons with a C-C double bond.

65
Alkenes

• ethene (or ethylene)
• propene
• etc

66
Ethene
1) Draw carbon atoms
67
Ethene
2) Fill in C-C bonds
C
C
68
Ethene
3) Fill in hydrogen atoms
H
H
C
C
H
H
Notice the shape!!
C2H4
69
2-pentene
CH
CH
CH3
CH2
CH3
1
2
3
4
5
C5H10
70
1-pentene
CH
CH2
CH2
CH2
CH3
1
2
3
4
5
C5H10
71
1-pentene
CH2 CH CH2
CH2 CH3


H2C CH CH2
CH2 CH3


C C


H
H
CH2 CH2 CH3


C5H10
H
72
Are 1-pentene and 2-pentene isomers?
CH
CH
CH3
CH2
CH3
1
2
3
4
5
CH
CH2
CH2
CH2
CH3
1
2
3
4
5
73
Whats in my gasoline?
n-alkanes (straight chain)
Aromatics
15-25
iso-alkanes (branched)
20-30
15-25
lt1
20-30
Alkenes and Alkynes
Cycloalkanes
74
Aromatics

• Contain 1 or more benzene rings.

75
Fig.10.04a
Figure 10.4 p. 438
76
Figure 10.4 p. 438
77
(No Transcript)
78
Fig.10.04d
Figure 10.4 p. 438
79
Figure 10.4 p. 438
80
Because of its toxicity, gasoline only contains
TRACE amounts of benzene.
Then, what aromatics are in gasoline?
81
Toluene, C7H8
Benzene, with a methyl group attached
H
C
H
CH3
C
C
C
C
H
H
C
H
82
Toluene
CH3
Also called methylbenzene!!!
83
Isomers?
CH3
CH3
C7H8
NO!! They are the SAME MOLECULE
C7H8
84
Isomer Same chemical formula but different
chemical structure!!!
85
Xylenes
CH3
CH3
Benzene with TWO methyl groups attached.
86
Xylenes
NO!! Same molecule
Isomers?
CH3
H3C
CH3
CH3
87
Xylenes
YES
Isomers?
H3C
CH3
CH3
CH3
88
YES
Xylenes
H3C
Isomers?
CH3
CH3
CH3
89
Last but not least
90
CH3
CH2
What is this called?
Benzene with an ethyl group attached.
91
Ethylbenzene, C8H10
CH3
CH2
What is this called?
Benzene with an ethyl group attached.