1a.atomic structure of quantum mechnc.ppt

8/10/2019 1a.Atomic Structure of Quantum Mechnc.ppt

1/141

The Quantum-

Mechanical

Model of theAtom

2007, Prentice Hall

Chemistry: A Molecular Approach, 1stEd.

Nivaldo Tro

Roy Kennedy

Massachusetts Bay o!!unity olle"e#ellesley Hills, M$

Modi%ied &y

Kristian H. 'u"iyarto


2/141

Tro, he!istry( $ Molecular $))roach 2

The Behavior o% the *ery '!all

+ electrons are incredi&ly s!alla sin"le s)ec o% dust has !ore electrons than the

nu!&er o% )eo)le -ho have ever lived on earth+ electron &ehavior deter!ines !uch o% the

&ehavior o% ato!s

+ directly o&servin" electrons in the ato! isi!)ossi&le, the electron is so s!all thato&servin" it chan"es its &ehavior


3/141

What is this ?


4/141


5/141


6/141


7/141

Extreme (1)particle!

(2) (3) (4)

(5) (6) (7) Extreme ()

wave?!


8/141

Tro, he!istry( $ Molecular $))roach

$ Theory that E/)lains Electron Behavior

+ the "uantum-mechanical modele/)lains the !annerelectrons e/ist and &ehave in ato!s

+ hel)s us understand and )redict the )ro)erties o% ato!sthat are directly related to the &ehavior o% the electrons

-hy so!e ele!ents are !etals -hile others are non!etals

-hy so!e ele!ents "ain 1 electron -hen %or!in" an anion,

-hile others "ain 2

-hy so!e ele!ents are very reactive -hile others are

)ractically inert

and other Periodic )atterns -e see in the )ro)erties o% the

ele!ents


9/141


The Nature o% i"ht

its #ave Nature

+ li"ht is a %or! o% electroma#netic radiationco!)osed o% )er)endicular oscillatin" -aves, one %or the

electric %ield and one %or the !a"netic %ieldan electric %ield is a re"ion -here an electrically char"ed )article

e/)eriences a %orce

a !a"netic %ield is a re"ion -here an !a"netied )article e/)eriences

a %orce

+ all electro!a"netic -aves !ove throu"h s)ace at thesa!e, constant s)eed

3.00 / 10!4s in a vacuu! 5 the $%eed of li#ht& c


10/141


')eed o% Ener"y Trans!ission


11/141


Electro!a"netic Radiation


12/141


haracteriin" #aves

+ the am%litudeis the hei"ht o% the -avethe distance %ro! node to crestor node to trou"h

the a!)litude is a !easure o% ho- intense the li"htis 6 the lar"er the a!)litude, the &ri"hter the li"ht

+ the 'aelen#th& ()is a !easure o% the distancecovered &y the -ave

the distance %ro! one crest to the ne/tor the distance %ro! one trou"h to the ne/t, or the

distance &et-een alternate nodes


13/141


#ave haracteristics


14/141

#ave ani!ation

http://chapter_07/Present/Media/AACXJQX0.htmlhttp://chapter_07/Present/Media/AACXJQX0.html


15/141

Properties of Waves

Wavelength() is the distance between identical points onsuccessive waves.

Amplitudeis the vertical distance from the midline of a

wave to the peak or trough.7.1


16/141

Properties of Waves

Frequency() is the number of waves that pass through aparticular point in 1 second (Hz 1 c!cle"s).

#he speed (u) of the wave

$

7.1


17/141

%a$well (1&7') proposed that visible light consists of

electromagnetic waves.

Electromagnetic

radiationis the emission

and transmission of energ!

in the form of

electromagnetic waves.

peed of light (c) in vacuum '.** $ 1*&m"s

Allelectromagnetic radiation

$

=c

7.1


18/141


haracteriin" #aves

+ the fre"uenc& ()is the nu!&er o% -aves that)ass a )oint in a "iven )eriod o% ti!ethe nu!&er o% -aves 5 nu!&er o% cycles

units are hert, 8H9 or cycles4s 5 s

:1

1 H 5 1 s:1

+ the total ener"y is )ro)ortional to the a!)litudeand %re;uency o% the -aves

the lar"er the -ave a!)litude, the !ore %orce it has

the !ore %re;uently the -aves strie, the !ore total%orce there is


19/141


The Relationshi) Bet-een

#avelen"th and


20/141


E/a!)le 7.1: alculate the -avelen"th o% red

li"ht -ith a %re;uency o% .=2 / 101s:1

the unit is correct, the -avelen"th is a))ro)riate

%or red li"ht

*hec+,

olution,

>5 c, 1 n! 5 10:!

*once%t .lan,

/elation$hi%$,

5 .=2 / 101s:1, 8n!9

0ien,ind,

(s:19 8!9 8n!9

c=

!10

n!1

!10.=10=2.

1000.3c 71:

s1

:1s!

=

==

n!10.=!10

n!1!10.= 2

7 =


21/141


Practice 6 alculate the -avelen"th o% a radio

si"nal -ith a %re;uency o% 100.7 MH


22/141


!.210007.1

1000.3c1:

s

:1s!

=

==

1::1=

s10007.1MH1

s10MH00.71 =

Practice 6 alculate the -avelen"th o% a radio

si"nal -ith a %re;uency o% 100.7 MH

the unit is correct, the -avelen"th is a))ro)riate

%or radio-aves

*hec+,

ole,

>5 c, 1 MH 5 10=s:1

*once%t .lan,

/elation$hi%$,

5 100.7 MH, 8!9

0ien,ind,

(H9 8s:19 8!9

c

=

MH1

s10 :1=


23/141


olor

+ the color o% li"ht is deter!ined &y its -avelen"thor %re;uency

+ -hite li"ht is a !i/ture o% all the colors o% visi&le li"ht a $%ectrum

/edran"eello-0reenlueiolet

+ -hen an o&?ect a&sor&s so!e o% the -avelen"ths o%

-hite li"ht -hile re%lectin" others, it a))ears colored the o&served color is )redo!inantly the colors re%lected


24/141

2

#avelen"th @ $!)litude


25/141

Tro, he!istry( $ Molecular $))roach 2A

Electro!a"netic ')ectru!


26/141

Ty)e o% Radiation


27/141


ontinuous ')ectru!


28/141


The Electro!a"netic ')ectru!

+ visi&le li"ht co!)rises only a s!all %raction o%all the -avelen"ths o% li"ht 6 called theelectroma#netic $%ectrum

+ short -avelen"th 8hi"h %re;uency9 li"ht hashi"h ener"yradio-ave li"ht has the lo-est ener"y

"a!!a ray li"ht has the hi"hest ener"y

+ hi"h ener"y electro!a"netic radiation can)otentially da!a"e &iolo"ical !oleculesioniin" radiation


29/141


Ther!al !a"in" usin" n%rared i"ht

C i Hi h E R di i


30/141


Csin" Hi"h Ener"y Radiation

to Kill ancer ells


31/141

/5 c5 c4

5 '.** $ 1*&m"s/+.* $ 1*,Hz5 -.* $ 1*'m

adio wave

/ photon has a fre0uenc! of +.* $ 1*,Hz. onvert

this fre0uenc! into wavelength (nm). 2oes this fre0uenc!

fall in the visible region3

5 -.* $ 1*14nm

7.1


32/141


nter%erence

+ the interaction &et-een -aves is calledinterference

+ -hen -aves interact so that they add to !ae alar"er -ave it is called con$tructie interference-aves are in-%ha$e

+ -hen -aves interact so they cancel each other it iscalled de$tructie interference-aves are out-of-%ha$e


33/141


nter%erence


34/141


Di%%raction

+ -hen travelin" -aves encounter an o&stacle or o)enin"in a &arrier that is a&out the sa!e sie as the

-avelen"th, they &end around it 6 this is called

diffraction

travelin" )articles do not di%%ract

+ the di%%raction o% li"ht throu"h t-o slits se)arated &y adistance co!)ara&le to the -avelen"th results in an

inter%erence )attern o% the di%%racted -aves+ an inter%erence )attern is a characteristic o% all li"ht

-aves

Di%% ti


35/141

Tro, he!istry( $ Molecular $))roach 3A

Di%%raction


36/141

Tro, he!istry( $ Molecular $))roach 3=

2:'lit nter%erence

h h l i %%


37/141


The Photoelectric E%%ect

+ it -as o&served that !any !etals e!it electrons -hen ali"ht shines on their sur%ace this is called the .hotoelectric Effect

+ classic -ave theory attri&uted this e%%ect to the li"htener"y &ein" trans%erred to the electron

+ accordin" to this theory, i% the -avelen"th o% li"ht is!ade shorter, or the li"ht -aves intensity !ade

&ri"hter, !ore electrons should &e e?ected re!e!&er( the ener"y o% a -ave is directly )ro)ortional to its

a!)litude and its %re;uency

i% a di! li"ht -as used there -ould &e a la" ti!e &e%oreelectrons -ere e!itted to "ive the electrons ti!e to a&sor& enou"h ener"y


38/141



Th Ph l i E%%


39/141



The Pro&le!

+ in e/)eri!ents -ith the )hotoelectric e%%ect, it-as o&served that there -as a !a/i!u!

-avelen"th %or electrons to &e e!ittedcalled the thre$hold fre"uenc

re"ardless o% the intensity

+ it -as also o&served that hi"h %re;uency li"ht-ith a di! source caused electron e!ission-ithout any la" ti!e


40/141


Einsteins E/)lanation

+ Einstein )ro)osed that the li"ht ener"y -asdelivered to the ato!s in )acets, called "uantaor %hoton$

+ the ener"y o% a )hoton o% li"ht -as directly)ro)ortional to its %re;uencyinversely )ro)ortional to it -avelen"th

the )ro)ortionality constant is called .lanc+$

*on$tant& (h)and has the value =.=2= / 10:3

F>s

chhE

==


41/141

Photoelectric e%%ect ani!ation

http://chapter_07/Present/Media/PhotoelectricEffect.htmlhttp://chapter_07/Present/Media/PhotoelectricEffect.html


42/141


E/a!)le 7.2: alculate the nu!&er o% )hotons in a laser

)ulse -ith -avelen"th 337 n! and total ener"y 3.3 !F

ole,

E5hc4, 1 n! 5 10:!, 1 !F 5 10:3F, E)ulse4E)hoton5 G )hotons

*once%t .lan,

/elation$hi%$,

5 337 n!, E)ulse5 3.3 !Fnu!&er o% )hotons

0ien,ind,

hcE)hoton=

n!1

!10

( )( ) F10A.A1037.31000.310=2=.=hcE 1

!7

:1s!

sF

3

)hoton

=

==

!1037.3n!1

!10n!1037.3 7

2

=

(n!9 8!9 E)hotonnu!&er

)hotons

)hoton

)ulse

E

E

F103.3!F1

F10!F3.3 3

3

=

)hotons10.=

F10A.A

F103.3)hotonso%nu!&er

1A

3

3

=

=


43/141


Practice 6 #hat is the %re;uency o% radiation

re;uired to su))ly 1.0 / 102F o% ener"y %ro!

.A / 1027

)hotons


44/141


( ) 1:73

2=

s10.1sF10=2=.=

F107=1.1

h

Ephoton =

==

#hat is the %re;uency o% radiation re;uired to su))ly

1.0 / 102F o% ener"y %ro! .A / 1027)hotons

ole,

E5h, Etotal5 E)hoton>G )hotons

*once%t .lan,

/elation$hi%$,

Etotal5 1.0 / 102

F, nu!&er o% )hotons 5 .A / 1027

0ien,

ind,

=h

E)hoton8s:19E)hoton

nu!&er

)hotons

)hotonso%nu!&er

E total

F107=1.110A.

F100.1 2=27

2

Ephoton=

=


45/141

Tro, he!istry( $ Molecular $))roach A

E?ected Electrons

+ 1 )hoton at the threshold %re;uency has ?ustenou"h ener"y %or an electron to esca)e the ato!indin# ener#&

+ %or hi"her %re;uencies, the electron a&sor&s !oreener"y than is necessary to esca)e

+ this e/cess ener"y &eco!es inetic ener"y o% the

e?ected electronKinetic Energy5Ephoton Ebinding

KE = h:

' t


46/141

Tro, he!istry( $ Molecular $))roach =

')ectra

+ -hen ato!s or !olecules a&sor& ener"y, that ener"y is

o%ten released as li"ht ener"y %ire-ors, neon li"hts, etc.

+ -hen that li"ht is )assed throu"h a )ris!, a )attern isseen that is uni;ue to that ty)e o% ato! or !olecule 6 the

)attern is called an emi$$ion $%ectrumnon:continuouscan &e used to identi%y the !aterial

%la!e tests

+ Ryd&er" analyed the s)ectru! o% hydro"en and %ound

that it could &e descri&ed -ith an e;uation that involvedan inverse s;uare o% inte"ers

=

22

21

1:7

n

1

n

1!1007.1

1

E/citin" Ias $to!s to E!it i"ht


47/141


E/citin" Ias $to!s to E!it i"ht

-ith Electrical Ener"y

H" He H


48/141


E!ission ')ectra

E/a!)les o% ')ectra


49/141


E/a!)les o% ')ectra

J/y"en s)ectru!

Neon s)ectru!

Line Spectra5 s)eci%ic -avelen"ths

are e!itted characteristic o% ato!s

denti%yin" Ele!ents -ith
http://wps.prenhall.com/wps/media/objects/166/170213/LinePairinSodiumSpectrum.htmlhttp://wps.prenhall.com/wps/media/objects/166/170213/LinePairinSodiumSpectrum.html


50/141

Tro, he!istry( $ Molecular $))roach A0

denti%yin" Ele!ents -ith


51/141


52/141

Tro, he!istry( $ Molecular $))roach A2

E!ission vs. $&sor)tion ')ectra

')ectra o% Mercury


53/141

7.'

5ine 6mission pectrum of H!drogen /toms


54/141

7.'

B h M d l


55/141

Tro, he!istry( $ Molecular $))roach AA

Bohrs Model

+ Neils Bohr )ro)osed that the electrons could only havevery s)eci%ic a!ounts o% ener"y %i/ed a!ounts5 "uanti8ed

+ the electrons traveled in or&its that -ere a %i/eddistance %ro! the nucleus$tationar $tate$ there%ore the ener"y o% the electron -as )ro)ortional the

distance the or&it %ro! the nucleus

+ electrons e!itted radiation -hen they L?u!)ed %ro!

an or&it -ith hi"her ener"y do-n to an or&it -ith lo-erener"y the distance &et-een the or&its deter!ined the ener"y o% the

)hoton o% li"ht )roduced

Bohrs Model of


56/141

1. ecan onl! have specific(0uantized) energ!

values

4. light is emitted as e

moves from one energ!level to a lower energ!

level

Bohr s Model of

the Atom (1913)

6n H ( )1

n4

n(principal 0uantum number) 14'8

H(!dberg constant) 4.1& $ 1*1&9

7.'

E = hn


57/141

E = hn

7.'

alculate the wavelength (in nm) of a photon


58/141

Ephoton 4.1& $ 1*1&

9 $ (1"4- 1":)Ephoton E 1.-- $ 1*1:9

+.+' $ 1*',(9;s) $ '.** $ 1*& (m"s)"1.-- $ 1*1:9

14&* nm

alculate the wavelength (in nm) of a photon

emitted b! a h!drogen atom when its electron

drops from the n - state to the n ' state.

Ephoton h$ c"

h$ c " Ephoton

i f

E RH( )1

n41

n4Ephoton

7.'


59/141

Tro, he!istry( $ Molecular $))roach A

Bohr Model o% H $to!s

The 9ia#ram of Ele+tronic Tran$ition$ for :man .a$chen


60/141

The 9ia#ram of Ele+tronic Tran$ition$ for :man-.a$chen-

almer :ine$ %ectra accodin# to ohr

Lyman Balmer Paschen

n- E; cm-1

1

2

3

4

(a) (a)

Pao?ang @i (J. Chem. Ed.1:,7 Aol. 4, -+7)

(b) Bncle Wiggl! (J. Chem. Ed.1:&' Aol. +* -+4)

(c) 2arse! sebagai Cpohon natal PascalD( (J. Chem. Ed.1:&& Aol. +- 1*'+)

(4)

"s

3s

-s

s

+s

0s

"p

3p

-p

p

+p

0p

3d

-d

d

+d

-f

f


130/141

Electron on%i"uration o% $to!s in

their Iround 'tate


131/141

their Iround 'tate

+ Electron con%i"uration 5 order o% %illin" -ithelectrons nu!&er o% electrons in that su&shell-ritten as a su)erscri)t

Kr 5 3= electrons5 1s2

2s2

2p=

3s2

3p=

31

1a.atomic structure of quantum mechnc.ppt

Documents