timberlake lectureplus 19991 chapter 11 haloalkanes, alkenes, and alkynes functional groups...
TRANSCRIPT
Timberlake LecturePLUS 1999 1
Chapter 11Haloalkanes, Alkenes, and Alkynes
Functional Groups
Haloalkanes
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Functional Groups
Part of an organic molecule where chemical reactions take place
Composed of an atom or group of atoms Replace a H in the corresponding alkane Provide a way to classify organic
compounds
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Some Types of Functional Groups
Haloalkane -F, -Cl, -Br CH3Cl
Alcohol -OH CH3OH
Ether -O- CH3-O-CH3
Aldehyde
KetoneC
O
CH3CH
O
C H
O
CH3CCH3
O
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More Functional Groups
Carboxylic acid -COOH CH3COOH
Ester -COO- CH3COOCH3
Amine -NH2 CH3NH2
Amide -CONH2 CH3CONH2
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Haloalkanes
An alkane in which one or more H atoms is replaced with a halogen (F, Cl, Br, or I)
CH3Br 1-bromomethane
Br (methyl bromide)
CH3CH2CHCH3 2-bromobutane
Cl
chlorocyclobutane
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Learning Check HA1
Name the following:
Br
Cl
Cl
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Solution HA1
Name the following:
bromocyclopentane
1,3-dichlorocyclohexane
Br
Cl
Cl
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Substituents
List other attached atoms or group in alphabetical order
Br = bromo, Cl = chloro
Cl Br
CH3CHCH2CHCH2CH2CH3
4-bromo-2-chloroheptane
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Learning Check HA2
The name of this compound is:
Cl CH3
CH3CH2CHCH2CHCH3
1) 2,4-dimethylhexane
2) 3-chloro-5-methylhexane
3) 4-chloro-2-methylhexane
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Solution HA2
The name of this compound is:
Cl CH3
CH3CH2CHCH2CHCH3
3) 4-chloro-2-methylhexane
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Haloalkanes as Anesthetics
Halothane (Fluothane) F Cl
F C C Br
F HFluothane is a haloalkane that is widely used as an anesthetic, which is a compound that decreases the ability of the nerve cells to conduct pain.
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Ozone Layer
Ozone layer
Stratosphere
(10-30 miles
Above Earth)
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Chlorofuorocarbons (CFCs and the Ozone Layer
ozone O3 layer absorbs most of the sun’s harmful radiation.
CFCs - chlorofluorocarbons - are depleting that ozone layer.
CFCs are used as Freons in refrigeration,
air conditioning, and foam insulation.
Their use in spray cans is no longer allowed.
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Chlorofuorocarbons and the Ozone Layer
In the stratosphere, the CFCs react with
the high-energy UV radiation from the sun
UV light
CF2Cl2 CF2Cl + Cl
Freon-12 free radical
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Chlorofuorocarbons and the Ozone Layer
To become stable, the Cl acquires an electron from ozone O3 and produces ClO.
Cl + O3 ClO + O2
The presence of ClO in the atmosphere is an indicator of the disappearance of ozone.
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Impact of Loss of Ozone Layer
According to the National Academy of
Sciences, each 1% loss of ozone increases
by 2% the amount of UV radiation reaching
the earth. More UV radiation means more
skin cancer and cataracts in humans, more
intense photochemical smog, and lower crop
yields.