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Topics for Today. What is in my gasoline? Burning a gallon of gasoline…. Readings for Today. 3.6 Quantitative Concepts: Mass 3.7 Quantitative Concepts: Molecules and Moles. Topics for Wednesday. Burning a gallon of gasoline. Where does my gasoline come from?. Readings for Wednesday.
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Topics for Today What is in my gasoline? Burning a gallon of gasoline…
Readings for Today • 3.6 Quantitative Concepts: Mass • 3.7 Quantitative Concepts: Molecules and Moles
Topics for Wednesday • Burning a gallon of gasoline. • Where does my gasoline come from?
Readings for Wednesday • 3.6 Quantitative Concepts: Mass • 3.7 Quantitative Concepts: Molecules and Moles
Topics for Friday • Exam #2
Topics for Monday • Greenhouse Earth!
Topics for Today What is in my gasoline? Burning a gallon of gasoline…
Gasoline A volatilemixture of flammable liquid hydrocarbons derived chiefly from crude petroleum and used principally as a fuel for internal-combustion engines.
Gasoline A volatilemixture of flammable liquid hydrocarbons derived chiefly from crude petroleum and used principally as a fuel for internal-combustion engines. What is “volatile?”
N2 + O2 2NO NO + O2 + .OH + VOCs NO2+ VOCs high temp Easily goes into the vapor phase VOC = Volatile Organic Compounds Contains C
Some VOCs Methane (1 carbon) Ethane (2 carbons) Propane (3 carbons) Butane (4 carbons) Octane (8 carbons)
Gasoline A volatilemixture 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
Gasoline A volatilemixture of flammable liquid hydrocarbons derived chiefly from crude petroleum and used principally as a fuel for internal-combustion engines. What is a “mixture?”
Is gasoline heterogeneous or homogenous? Matter Elements Pure Substances Mixtures Compounds Heterogeneous Homogeneous
Gasoline A volatilemixture of flammable liquid hydrocarbons derived chiefly from crude petroleum and used principally as a fuel for internal-combustion engines. What is “flammable?”
Complete combustion of methane CH4 + 2O2 CO2 + 2H2O Undergoes combustion!
Gasoline A volatilemixture of flammable liquid hydrocarbons derived chiefly from crude petroleum and used principally as a fuel for internal-combustion engines. What is a “hydrocarbon?”
H 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 -C-H 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
Gasoline A volatilemixture 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?”
Some hydrocarbons Methane Ethane Propane Butane Octane
Some hydrocarbons Methane Ethane Propane Butane Octane
Gasoline A volatilemixture 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!!
What’s in my gasoline? n-alkanes (straight chain) Aromatics 15-25% iso-alkanes (branched) 20-30% 15-25% <1% 20-30% Alkenes and Alkynes Cycloalkanes
What’s in my gasoline? n-alkanes (straight chain) Aromatics 15-25% iso-alkanes (branched) 20-30% 15-25% <1% 20-30% Alkenes and Alkynes Cycloalkanes
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.
n-butane H H H H H C C H C C H H H H n-butane, C4H10
n-butane OR H H H H H C C H C C H H H H n-butane, C4H10
Condensedstructural formula! CH3-CH2-CH2-CH3 n-butane, C4H10
n-butane Figure 10.3 page 436
n-pentane Be able to draw and name these structures from methane to octane! H H H H H H C C C H C C H H H H H n-pentane, C5H12
What’s in my gasoline? n-alkanes (straight chain) Aromatics 15-25% iso-alkanes (branched) 20-30% 15-25% <1% 20-30% Alkenes and Alkynes Cycloalkanes
Compare CH3-CH2-CH2-CH3 n-butane, C4H10
Compare H H H H H C C H C C H H H H n-butane, C4H10
isobutane Structural Formula H H H C H H H C C H C H H H isobutane, C4H10
Condensedstructural formula! CH3 CH3-CH-CH3 isobutane, C4H10
n-butane Figure 10.3 page 436
iso-butane Figure 10.3 page 436
n-butane and isobutane are isomers! Isomer = Same chemical formula but different chemical structure!!!
isobutane Also known as H H H C H H H C C H C H H H isobutane, C4H10
isobutane Also known as H 2-methylpropane H H C H H H C C H C H H H isobutane, C4H10
isobutane Also known as H 2-methylpropane H H C H H H C C H C 1 2 3 H H H isobutane, C4H10
isobutane Also known as methyl, .CH3 H 2-methylpropane H H C H H H C C H C 1 2 3 H H H isobutane, C4H10
Some VOCs Methane (1 carbon) Ethane (2 carbons) Propane (3 carbons) Butane (4 carbons) Octane ( 8 carbons)
Methyl (1 carbon) .CH3 Ethyl (2 carbons) Propyl (3 carbons)
n-octane Not too much of this in gasoline… CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH3 Chemical formula? C8H18
isooctane Isomers!! CH3 CH3 CH3-C-CH2-CH-CH3 CH3 Chemical formula? C8H18
2-methylpentane CH3 CH3 CH CH2 CH2 CH3 Chemical formula?
2-methylpentane CH3 CH3 CH CH2 CH2 CH3 Chemical formula? C6H14
2-methylpentane Same or different? CH3 CH3 CH CH2 CH2 CH3 =? CH3 CH CH2 CH2 CH3 CH3