Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
1/30/2017 11:08 AM
Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Copyright © 2017 Dan Dill [email protected]
TP HowmanypairsofelectronsaresharedbyeachOandtheC
offormate,HC O O
20%
20%
20%
20%
20%
1.
2.
3.
4.
5.
Monday, January 30, 2017
• Complete:PolyatomicMOrecipe:Formate,HC O O
bonds
1pair 2electrons
1½pair 3electrons
2pair 4electrons
Somethingelse
TheanswerisdifferentforthetwoO‐Cbonds
HC(O)O‒
sp2
Next:Continuech11:Molecularspeedsandtheirdistribution;realgases
attractionandsize
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σ framework
Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
HC(O)O−
Copyright © 2017 Dan Dill [email protected]
π framework
2pairsin delocalized π framework
9pairsinLewisstructure,7pairsinσ framework,andso2
pairsin delocalized π framework.
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delocalized π
Begin Mahaffyetal.,Chapter11:StatesofMatter
• Behaviorofgases:Macroscopicversusmicroscopicunderstanding
• Kineticmoleculartheory,PDF:http://goo.gl/njf3em
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Lecture 5 CH102 A1 (MWF 9:05 am)
1pairinπ bonding and1pairinπn nonbonding ;
bondorder1
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
1/30/2017 11:08 AM
Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Copyright © 2017 Dan Dill [email protected]
20%
20%
20%
20%
20%
1.
2.
3.
4.
5.
1pair 2electrons
1½pair 3electrons
2pair 4electrons
Somethingelse
TheanswerisdifferentforthetwoO‐Cbonds
14%
14%
14%
14%
14%
14%
14%
Response
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
10
1.
2.
3.
4.
5.
6.
7.
1pair 2electrons
1½pair 3electrons
2pair 4electrons
2½pair 5electrons
3pair 6electrons
Somethingelse
TheanswerisdifferentforthetwoOatoms
Response
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
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TP AcontainerofvolumeV isfilledwithagasat20oC. IfV isdecreased
whilekeepingT constant ,pressureP exertedbythegasonthewallsofthe
containermust…
Behaviorofgases
25%
25%
25%
25%
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Copyright © 2017 Dan Dill [email protected]
Copyright © 2017 Dan Dill [email protected]
Groupquiz HowmanylonepairsofelectronsareoneachO
offormate,HC O O
TP HowmanypairsofelectronsaresharedbyeachOandtheC
offormate,HC O O
1.
2.
3.
4.
godown
staythesame
goup
Furtherinformationneeded
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
1/30/2017 11:08 AM
Copyright © 2017 Dan Dill [email protected]
Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Macroscopic behavior
Macroscopic behavior
Verylikelyyouknowandhavealotofexperienceworkingwiththeidealgas
equation relatingP,T,V andn,…
From
PV R nT
Copyright © 2017 Dan Dill [email protected]
PV R nT
weknowthatifV isdecreased whilekeepingT constant ,thepressureP
exertedbythegasonthewallsofthecontainermustgoup,sincetheleft‐hand
sideoftheequationisunchanged.
Theconstantofproportionalityisthegasconstant…
R 8.314J / Kmol
Thisisanexampleofmacroscopic understanding.
Ourgoalistounderstandthiskindofbehavioratamicroscopic level.
Thatis,attheleveloftheindividualparticlesofthegas.
Ourmethodiscalledthekineticmoleculartheoryofgases.
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Copyright © 2017 Dan Dill [email protected]
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Microscopic behavior
Kinetic-molecular theory of gases
Ourgoalistounderstandthiskindofbehavioratamicroscopic level.
Goal:GetmicroscopicexpressionforpressureP
Thatis,attheleveloftheindividualparticlesofthegas.
Copyright © 2017 Dan Dill [email protected]
Keyidea1:Pressureisduetoforceexertedbyparticlesduringcollisionswith
thecontainerwalls
Ourmethodiscalledthekineticmoleculartheoryofgases.
Keyidea2:Forceisduetomomentumchangeincollisionwiththecontainer
walls.
Note:Hereupper‐caseP isusedforpressureandlower‐casep isusedfor
momentum.
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Copyright © 2017 Dan Dill [email protected]
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
1/30/2017 11:08 AM
Copyright © 2017 Dan Dill [email protected]
Kinetic-molecular theory of gases
Copyright © 2017 Dan Dill [email protected]
Kinetic-molecular theory of gases
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Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
Lecture 5 CH102 A1 (MWF 9:05 am) Spring 2017
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Copyright © 2017 Dan Dill [email protected]
Kinetic-molecular theory of gases
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