Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
1/24/2017 6:37 PM
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
TP IntheIRspectrumshownofCH3Br,theabsorptionnear3000cm
to…
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C
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Lecture 9 CH101 A1 (MWF 9 am)
Wednesday, September 28, 2016
Brstretch
Hstretch
C Brsymmetricstretch
C Brantisymmetricstretch
Fortoday…
• Complete:IRspectra
• Ch4: secs1,3,and4only :Howtheatmospherewarms
ThinkaboutIte4.4:Collisionalheatinghttp://goo.gl/vQ0Nz
ThinkaboutIte4.5:IRwindowshttp://goo.gl/I8IGz
Nextlecture:BeginCh5:Chemicalequations&dynamicequilibrium
Response
Counter
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
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Copyright © 2016 Dan Dill [email protected]
Resonance in light-matter interaction
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
What is being displayed in an IR spectrum?
Demonstration:Taleofthreefrequencies
Frequenciesmatch→response
Frequenciesdonotmatch→“transparency”
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Copyright © 2016 Dan Dill [email protected]
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Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
1/24/2017 6:37 PM
Copyright © 2016 Dan Dill [email protected]
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
What is being displayed in an IR spectrum?
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Copyright © 2016 Dan Dill [email protected]
Constitutional (structural) Isomers
1
isdue
Brstretch
Hstretch
C Brsymmetricstretch
C Brantisymmetricstretch
Response
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Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
TP IntheIRspectrumshownofCH3Br,theabsorptionnear3000cm
to…
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
10
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Copyright © 2016 Dan Dill [email protected]
C2H6O: Dimethyl ether
Ethanol:
Dimethyl ether:
Thesehavethesamemolecularionpeak,andsoarehardtodistinguishusing
massspectroscopy.
TheycanbedistinguishedeasilyusingIRspectroscopy.
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Copyright © 2016 Dan Dill [email protected]
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Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
1/24/2017 6:37 PM
Copyright © 2016 Dan Dill [email protected]
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
Quiz Whatmotionmustaccountfortheabsorptioninthe3600cm
C2H6O: Ethanol
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Copyright © 2016 Dan Dill [email protected]
region?
COstretch
CCstretch
CHstretch
OHstretch
Somethingelse
Response
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Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
1
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
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Copyright © 2016 Dan Dill [email protected]
Earth’s radiation balance
Howtheatmospherewarms
Atmosphere
transparent
tovisible
light
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Copyright © 2016 Dan Dill [email protected]
IR light
emitted from
heated land
masses
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Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
Lecture 9 CH101 A1 (MWF 9 am) Fall 2016
1/24/2017 6:37 PM
Copyright © 2016 Dan Dill [email protected]
e4.4: Heating due to Greenhouse Gases
ThinkaboutIte4.4:http://goo.gl/vQ0Nz
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Copyright © 2016 Dan Dill [email protected]
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