ElectronElectronss

Model of atoms

Model of atoms

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Light was first recognized as manifestation of electromagnetic energy and it was called electromagnetic radiation

The Wave Nature of Light

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As

As

ele

ctro

magneti

c w

ave

ele

ctro

magneti

c w

ave, ,

light

has

som

e c

hara

cteri

stic

s

light

has

som

e c

hara

cteri

stic

s

in c

om

mon w

ith a

ll fo

rms

of

in c

om

mon w

ith a

ll fo

rms

of

ele

ctro

magneti

c energ

y

ele

ctro

magneti

c energ

y

• Produced by motion of

Produced by motion of

electrically charged

electrically charged particlesparticles• Move through vacuum (at

Move through vacuum (at

3.00 x 103.00 x 10 88 m/s or 186,282

m/s or 186,282

mi/hr), air and other

mi/hr), air and other substancessubstances• Have characteristic

Have characteristic wavelengths/frequencies

wavelengths/frequencies• Visible radiation has

Visible radiation has wavelengths between

wavelengths between

400 nm (violet) and 750

400 nm (violet) and 750

nm (red)nm (red)

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http://college.hmco.com/chemistry/shared/media/animations/electromagneticwave.html

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WaveWave: disturbance of medium which : disturbance of medium which transports energy without transports energy without permanently transporting matterpermanently transporting matter

MediumMedium

Substance or material that carries Substance or material that carries wavewave

Merely carries wave from source to Merely carries wave from source to other locationother location

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Light is a repeating waveform in motion

(amt. energy found in wave)

Rest Position: no energy present

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Frequency, wavelength, and velocity Frequency, wavelength, and velocity are inversely proportional to each are inversely proportional to each

otherother

If frequency If frequency ↑↑, wavelength , wavelength ↓↓ Ex. Purple light has a frequency of 7.42 x Ex. Purple light has a frequency of 7.42 x

10101414 Hz.  What is its wavelength? Hz.  What is its wavelength?

c = c = 3.00 x 103.00 x 1088 m/s = m/s = 7.42 x 107.42 x 101414 Hz ( Hz ())

= 4.04 x 10= 4.04 x 10-7-7

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Ein

stein

succ

ess

ful

Ein

stein

succ

ess

ful

expla

ined p

hoto

-ele

ctri

c

expla

ined p

hoto

-ele

ctri

c

eff

ect

wit

hin

conte

xt o

f

eff

ect

wit

hin

conte

xt o

f quantu

m p

hysi

cs

quantu

m p

hysi

cs

PhotonsPhotons: packets of

: packets of

energy that make up

energy that make up

lightlight Each carries specific

Each carries specific energy related to its

energy related to its wavelengthwavelength Photons of short

Photons of short wavelength (

wavelength (blue lightblue light) )

carry more energy

carry more energy than long wavelength

than long wavelength

((red lightred light) photons

) photons

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Part

icula

te

Part

icula

te

Theory

of

Lig

ht

Theory

of

Lig

ht

Light is series of energy

Light is series of energy

packets passing through

packets passing through

spacespace Size of energy packets

Size of energy packets

vary/change color of light

vary/change color of light

QuantizedQuantized: electron limited

: electron limited

to specific quantities of

to specific quantities of

energy, not random value of

energy, not random value of

energyenergy Distance between energy

Distance between energy

packets = packets = wavelength

wavelength

# photons passing point in

# photons passing point in

period of time =

period of time = frequencyfrequency

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One o

f si

mple

st

One o

f si

mple

st

work

ing m

odels

of

work

ing m

odels

of

ato

m d

eve

loped b

y

ato

m d

eve

loped b

y N

iels

N

iels

Bohr

Bohr

Suggested H’s electron

Suggested H’s electron

moves around nucleus

moves around nucleus

in only certain allowed

in only certain allowed

orbitsorbits Smaller orbit, lower

Smaller orbit, lower

energy level

energy level Larger orbit, higher

Larger orbit, higher

energy level

energy level Electron can have

Electron can have different energy levels

different energy levels

Ground state

Ground state: lowest

level Excited state

Excited state: atom

gains energy

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Assigned quantum number, Assigned quantum number, n, to each orbit, to each orbit

Electron in ground state (1Electron in ground state (1stst energy level, n = 1) energy level, n = 1)

Does not radiate energyDoes not radiate energy

Quantum jumpQuantum jump: electron moves from one : electron moves from one energy level to another by gaining energy energy level to another by gaining energy (excited state) or losing energy (ground state) in (excited state) or losing energy (ground state) in continuously changing amounts continuously changing amounts • Electron drops from higher Electron drops from higher

to lower energy orbitto lower energy orbit• Photon with specific Photon with specific

energy emitted as lightenergy emitted as light• Shown as different Shown as different

colored line spectrums colored line spectrums ((atomic spectrumatomic spectrum))

• Every element has its Every element has its ownown

Atomic emission Atomic emission spectrum spectrum (amount of (amount of electromagnetic radiation of electromagnetic radiation of each frequency gas emits when each frequency gas emits when heated/excited)heated/excited) Photon hits metal, is absorbed as Photon hits metal, is absorbed as

electron takes up energyelectron takes up energy Einstein deduced each photon Einstein deduced each photon

possesses energypossesses energy Different metals require different Different metals require different

minimum frequencies for electrons minimum frequencies for electrons to exhibit to exhibit photoelectric effectphotoelectric effect Above threshold frequency, # Above threshold frequency, #

electrons ejected depend on electrons ejected depend on intensity of lightintensity of light

If photon’s frequency below If photon’s frequency below minimum, electron remains minimum, electron remains bound to metal surfacebound to metal surface

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http://college.hmco.com/chemistry/shared/media/animations/h2linespectrum.html

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Fe

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•Ephoton = nhν •n = # photons•h = Planck's constant, 6.626 x 10-34 J·s•ν= frequency of radiation

Convert wavelength from nanometers to meters:1 x 101 x 10-9-9 meters = 1 nm meters = 1 nm

http://www2.wwnorton.com/college/chemistry/gilbert/tutorials/interface.swf?chapter=chapter_03&folder=emission_absorption

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Groups of lines observed in Groups of lines observed in emission spectrum of hydrogen emission spectrum of hydrogen

atomsatoms

UVUV vviissiibblle e IRIR IR IR IR IR

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Calculate the energy of a photon of yellow Calculate the energy of a photon of yellow light with a frequency of 5.09 x 1014 s-1. light with a frequency of 5.09 x 1014 s-1. E= nhn =E= nhn = (1)(6.626 x 10(1)(6.626 x 10-34-34 J J..s)(5.09 x 10s)(5.09 x 101414 s-1)= 3.37 x 10 s-1)= 3.37 x 10 -19-19 J J

Calculate the energy of a photon of Calculate the energy of a photon of wavelength 5.00 x 10wavelength 5.00 x 1044 nm (infrared). nm (infrared). E = nhn = nhc/l =E = nhn = nhc/l = (1)(6.626 x 10(1)(6.626 x 10-34-34 J J··s)(3.00 x 10s)(3.00 x 1088 m/s) m/s)

(5.00 x 10(5.00 x 10-5-5 m) m)

= 3.98 x 10= 3.98 x 10-21-21 J J

Calculate energy of mole of photons of Calculate energy of mole of photons of yellow light with a frequency of 5.09 x 10yellow light with a frequency of 5.09 x 101414 s- s-1. 1. E = nhn = (6.022 x 10E = nhn = (6.022 x 102323)(6.626 x 10)(6.626 x 10-34-34 J J··s) (5.09 x 10s) (5.09 x 101414 s s-1-1) )

= 2.03 x 10= 2.03 x 1055 J J

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What is the frequency in hertz of blue light having a What is the frequency in hertz of blue light having a wavelength of 425 nm? wavelength of 425 nm? 7.06 X 107.06 X 101414 Hz Hz

A certain substance strongly absorbs infrared light A certain substance strongly absorbs infrared light having a wavelength of 6,500 nm.  What is the frequency having a wavelength of 6,500 nm.  What is the frequency in hertz of this light? in hertz of this light? 4.62 X 104.62 X 101313 Hz Hz

Yellow light has a wavelength of 600 nm. What is its Yellow light has a wavelength of 600 nm. What is its frequency in hertz? frequency in hertz? 5.00 X 105.00 X 101414 Hz Hz

Green light has a wavelength of 550 nm. What is its Green light has a wavelength of 550 nm. What is its frequency in hertz? frequency in hertz? 5.45 X 105.45 X 101414 Hz Hz

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Intense microwaves have a frequency of 9.5 X 10Intense microwaves have a frequency of 9.5 X 101111 Hz. Hz. What is the wavelength of these particular microwaves? What is the wavelength of these particular microwaves? 3.16 X 103.16 X 10-4-4 m  =  0.316 mm = 316 micrometers = 3.16 X 10 m  =  0.316 mm = 316 micrometers = 3.16 X 1055 nm nm

Infrared waves can be seen if you look down the railroad Infrared waves can be seen if you look down the railroad tracks or a road on a hot day. They heat the air as they go tracks or a road on a hot day. They heat the air as they go past causing the air to refract or bend the light.  If infrared past causing the air to refract or bend the light.  If infrared rays of 9.75 X 10rays of 9.75 X 101313 Hz are being reflected off the tracks or Hz are being reflected off the tracks or road what will be the size of  the wavelengths in road what will be the size of  the wavelengths in micrometers? micrometers? 3.08 X 103.08 X 10-6-6 m  = 3.08 micrometers m  = 3.08 micrometers

A sunbather forgot their sunblock. On the beach they get a A sunbather forgot their sunblock. On the beach they get a unheathy dose of UV radiation of 5.66 X 10unheathy dose of UV radiation of 5.66 X 101616 Hz.  What is Hz.  What is the wavelength of these particular UV waves? the wavelength of these particular UV waves? 5.30 X 105.30 X 10-9-9 m  = 5.00 nm m  = 5.00 nm

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Sodium vapor lamps are used to sometimes light Sodium vapor lamps are used to sometimes light streets. If the frequency of the light coming from streets. If the frequency of the light coming from them is 5.09 X 10them is 5.09 X 101414 Hz what is the energy in each Hz what is the energy in each photon? photon? 3.37 X 103.37 X 10-19-19 J/photon J/photon

What is the energy of each photon of red light that What is the energy of each photon of red light that has a frequency of 4.0 X 10has a frequency of 4.0 X 101414 Hz? Hz? 2.65 X 102.65 X 10-19-19 J/photon J/photon

Calculate the energy in joules/photon for green Calculate the energy in joules/photon for green light having a wavelength of 550 nm.light having a wavelength of 550 nm. 3.62 X 103.62 X 10-19-19 J/photon J/photon

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Microwaves are used to heat food in microwave Microwaves are used to heat food in microwave ovens. The microwave radiation is absorbed by ovens. The microwave radiation is absorbed by moisture in the food. This heats the water, and as moisture in the food. This heats the water, and as water becomes hot, so does the food.   How many water becomes hot, so does the food.   How many photons having a wavelength of 3.00 mm would photons having a wavelength of 3.00 mm would have to be absorbed by 1.00 g of water to raise its have to be absorbed by 1.00 g of water to raise its temperature by 1temperature by 1ooC? C? 6.63 X 106.63 X 10-19-19 J/photon; 6.31 X 10 J/photon; 6.31 X 102222 photons photons

The wavelengths of X-rays are much shorter than The wavelengths of X-rays are much shorter than those of ultraviolet or visible light. Show those of ultraviolet or visible light. Show quantitatively why continued exposure to X-rays is quantitatively why continued exposure to X-rays is more damaging than exposure to sunlight. more damaging than exposure to sunlight. X-rays: 6.63 X 10X-rays: 6.63 X 10-17-17 J/photon, UV rays: 6.63 X 10 J/photon, UV rays: 6.63 X 10-19-19

J/photon, X-rays are 100 times more powerful than UV J/photon, X-rays are 100 times more powerful than UV rays.rays.

Flame TestsFlame Tests Prepare 0.5 M solutions of Prepare 0.5 M solutions of

barium/calcium/potassium lithium/sodium/ and barium/calcium/potassium lithium/sodium/ and strontium chloride (nitrates can be used).strontium chloride (nitrates can be used).

Fold the end of a nichrome or platinum wire into a Fold the end of a nichrome or platinum wire into a ball and tap the straight end to a wooden stick.ball and tap the straight end to a wooden stick.

Dip the end into dilute hydrochloric acid, hold it in Dip the end into dilute hydrochloric acid, hold it in the burner until no color shows.the burner until no color shows.

Dip the end into a test tube of one of the Dip the end into a test tube of one of the solutions, place it in the flame, record color on solutions, place it in the flame, record color on chart.chart.

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Hom

ew

ork

Hom

ew

ork

:: Read 5.1, pp. 116-126

Read 5.1, pp. 116-126Q pg. 126, #8-10

Q pg. 126, #8-10Q pp. 146-147, #33,

Q pp. 146-147, #33, 36, 37, 65, 66, 70, 71,

36, 37, 65, 66, 70, 71,

74, 7674, 76

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By the mid-1920s, scientists convinced Bohr By the mid-1920s, scientists convinced Bohr atomic model was incorrect, formulated new atomic model was incorrect, formulated new

explanations of how electrons arranged in atomsexplanations of how electrons arranged in atoms

•de Broglie de Broglie (de-broy-lee) 1924•If light could act as both particles and waves, so could electrons•Since energy E of photon equals Planck’s constant times frequency f, or E = hf, momentum p of electron would equal Planck’s constant divided by wavelength

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Heis

enberg

’s

Heis

enberg

’s

Unce

rtain

ty P

rinci

ple

Unce

rtain

ty P

rinci

ple

applie

d d

e B

roglie

’s

applie

d d

e B

roglie

’s

hyp

oth

esi

shyp

oth

esi

s

Impossible to determine

Impossible to determine

with perfect accuracy

with perfect accuracy

both position and

both position and momentum of particle

momentum of particle

simultaneously

simultaneously

Making measurements on

Making measurements on

object alters location/

object alters location/

momentum enough to

momentum enough to

disturb accuracy of reading

disturb accuracy of reading

location/momentum

location/momentum

More certain we are about

More certain we are about

particle's position, less

particle's position, less

certain we are about its

certain we are about its

velocity, and vice versa

velocity, and vice versa

Bohr ran into trouble

Bohr ran into trouble

because he tried to

because he tried to

predict electron’s

predict electron’s movement too precisely

movement too precisely

Restricting electron to

Restricting electron to

certain locations and having

certain locations and having

it move in orbits violated

it move in orbits violated

Heisenberg Uncertainty

Heisenberg Uncertainty

PrinciplePrinciple

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Is li

ght

a w

ave

or

Is li

ght

a w

ave

or

a p

art

icle

? a p

art

icle

?

Electromagnetic

Electromagnetic radiation has dual

radiation has dual "personality“

"personality“ Acts like Acts like waves/photons with no

waves/photons with no

massmass Displays behaviors

Displays behaviors characteristic of any

characteristic of any

wave (reflection,

wave (reflection, refraction, diffraction,

refraction, diffraction,

interference, exhibits

interference, exhibits

Doppler effect) that

Doppler effect) that

would be difficult to

would be difficult to

explain with pure

explain with pure particle-view

particle-view

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Principles of Quantum Principles of Quantum Mechanics (Mechanics (SchrSchröödingerdinger))

Equation contains both wave and particle Equation contains both wave and particle termsterms

Electrons do not have planetary orbitElectrons do not have planetary orbit

Location of electron is probability, not Location of electron is probability, not certain positioncertain position

04/10/2334

Quantum TheoryQuantum Theory

Describes mathematically Describes mathematically wave properties of electrons wave properties of electrons and other very small particlesand other very small particles

Cloud shapes now called Cloud shapes now called orbitalsorbitals

3-D region around nucleus 3-D region around nucleus that indicates probable that indicates probable location of electron location of electron (“probability regions”)(“probability regions”)

Electrons not confined to Electrons not confined to fixed circular pathfixed circular path

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Quantum numbersQuantum numbers Specify properties of atomic Specify properties of atomic

orbitals/electrons in orbitalsorbitals/electrons in orbitals 11stst 3 from Schr 3 from Schröödinger equation (main energy dinger equation (main energy

level, shape, and orientation of orbital)level, shape, and orientation of orbital)

44thth is spin quantum number is spin quantum number

Electrons have Electrons have specific energy levels (1specific energy levels (1stst, , 22ndnd)) Different energy levels associated w/different Different energy levels associated w/different

orbitsorbits

Those nearer nucleus have lower energy than Those nearer nucleus have lower energy than those farther awaythose farther away

Electrons cannot exist between energy levelsElectrons cannot exist between energy levels

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Quantization of energyQuantization of energy Place a ball at the top of the stairs and roll it Place a ball at the top of the stairs and roll it

gently toward the flight of stairs.gently toward the flight of stairs. Observe the motion and intermittent resting Observe the motion and intermittent resting

points of the ball as it moves down the points of the ball as it moves down the stairs.stairs.

What is its final resting place on one step What is its final resting place on one step analogous to?analogous to?

Toss a small ball toward the top of the stairs Toss a small ball toward the top of the stairs with as little spin as possible.with as little spin as possible.

Where does it come to rest? What happens Where does it come to rest? What happens if you throw it harder (use more energy)?if you throw it harder (use more energy)?

What is the amount of energy you use What is the amount of energy you use analagous to?analagous to?

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Pri

nci

pal

Pri

nci

pal

Quantu

m

Quantu

m

Num

ber,

nN

um

ber,

n

Main Main energy level

energy level

occupied by electron/

occupied by electron/

size of orbital

size of orbital

As n becomes larger,

As n becomes larger,

atom becomes larger

atom becomes larger

and electron is further

and electron is further

away from nucleus

away from nucleus

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Cartesian coordinate systemCartesian coordinate system ((x, y,x, y, and and zz axes) as frame of reference; nucleus located axes) as frame of reference; nucleus located at originat origin

Boundary surface diagramsBoundary surface diagrams: volume of space : volume of space that encloses 90% probability of finding electron that encloses 90% probability of finding electron within orbital’s boundary surfaceswithin orbital’s boundary surfaces

Azi

muth

al

Azi

muth

al

Quantu

m N

um

ber,

Quantu

m N

um

ber,

ll

(an

gu

lar

mo

men

tum

)

(an

gu

lar

mo

men

tum

) ShapeShape of cloud

of cloud Divides shells into

Divides shells into subshells subshells (sublevels)

(sublevels) ((ll) in ) in each principal energy

each principal energy

level (level (ll = = n-1)n-1)

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• n = 1, 1 sublevel (s)

• n = 2, 2 sublevels (p)

• n = 3, 3 sublevels (d)

• n = 4, 4 sublevels (f)

• n = 1, 1 sublevel (s)

• n = 2, 2 sublevels (p)

• n = 3, 3 sublevels (d)

• n = 4, 4 sublevels (f)

Magneti

c M

agneti

c Q

uantu

m N

um

ber,

Quantu

m N

um

ber,

mm

ll (e

ffect

of

diff

ere

nt

ori

enta

tions

of

(eff

ect

of

diff

ere

nt

ori

enta

tions

of

orb

itals

1orb

itals

1stst o

bse

rved in

pre

sence

of

obse

rved in

pre

sence

of

magneti

c field

)

magneti

c field

)

Divides subshell into

Divides subshell into

orbitals orbitals which hold

which hold electronselectronsSpecifies 3-D

Specifies 3-D orientation of each

orientation of each orbital around

orbital around nucleusnucleus

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Each orbital has Each orbital has specificspecific # sublevels# sublevels

s has 1 sublevels has 1 sublevel

p has 3 sublevels (p has 3 sublevels (px, py, pzpx, py, pz))

d has 5 sublevels (d has 5 sublevels (dxy, dyz, dxz, dxdxy, dyz, dxz, dx22-y-y22, dz, dz22))

f has 7 sublevelsf has 7 sublevels

•http://college.hmco.com/chemistry/shared/media/animations/1sorbital.html •http://college.hmco.com/chemistry/shared/media/animations/2pxorbital.html •http://college.hmco.com/chemistry/shared/media/animations/2pyorbital.html •http://college.hmco.com/chemistry/shared/media/animations/2pzorbital.html•http://college.hmco.com/chemistry/shared/media/animations/3dxy_orbital.html •http://college.hmco.com/chemistry/shared/media/animations/3dxz_orbital.html •http://college.hmco.com/chemistry/shared/media/animations/3dz2orbital.html

Magneti

c Q

uantu

m

Magneti

c Q

uantu

m

Num

ber,

mN

um

ber,

mss

(spin

quantu

m

(spin

quantu

m

num

ber)

num

ber)

Specifies orientation of

Specifies orientation of

spin axis spin axis of electron

of electron Creates magnetic field

Creates magnetic field

because it spins, oriented in

because it spins, oriented in

one of two directions

one of two directions Pairs (

Pairs (diamagnetic

diamagnetic) not ) not

attracted to magnets

attracted to magnets Unpaired

Unpaired ((paramagnetic

paramagnetic) weakly ) weakly

attracted to magnets

attracted to magnets

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44

Each sublevel can contain Each sublevel can contain maximum of two electronsmaximum of two electrons

s has lowest energy (max 2 electrons)s has lowest energy (max 2 electrons)

p (max 6)p (max 6)

d (max 10)d (max 10)

f has highest energy (max 14)f has highest energy (max 14)

Must have Must have opposite spinsopposite spins

11stst electron to fill orbital has a electron to fill orbital has a ↑/+↑/+ spin spin

22ndnd electron to fill the orbital has a electron to fill the orbital has a ↓/-↓/- spin spin

You can use You can use //, N/S, , N/S, +/-+/-

04/10/23

45

Hom

ew

ork

Hom

ew

ork

::

Read 5.2, pp. 127-134

Read 5.2, pp. 127-134Q pg. 134, #13, 15, 16

Q pg. 134, #13, 15, 16

Q pg. 146, #42, 45,

Q pg. 146, #42, 45, 49, 52, 56, 49, 52, 56,

04/10/23

46

Aufb

au

Aufb

au (

“buildin

g u

p”

(“buildin

g u

p”

in G

erm

an)

in G

erm

an)

pri

nci

ple

pri

nci

ple

:

:

each

ele

ctro

n o

ccupie

s

each

ele

ctro

n o

ccupie

s

low

est

energ

y orb

ital

low

est

energ

y orb

ital

ava

ilable

ava

ilable

1.1. All orbitals related to energy

All orbitals related to energy

sublevel are of equal energy

sublevel are of equal energy

(All three 2p orbitals are of

(All three 2p orbitals are of

equal energy)

equal energy)2.2. Sublevels w/in principal

Sublevels w/in principal

energy level have diff.

energy level have diff.

energies (Three 2p orbitals

energies (Three 2p orbitals

are of higher energy than 2s

are of higher energy than 2s

orbital)orbital)3.3. In order of increasing energy,

In order of increasing energy,

sequence of energy sublevels

sequence of energy sublevels

within principal energy level is

within principal energy level is

s, p, d, and f

s, p, d, and f4.4. Orbitals within one principal

Orbitals within one principal

energy level can overlap

energy level can overlap

orbitals related to energy

orbitals related to energy

sublevels within another

sublevels within another

principal level (Orbital related

principal level (Orbital related

to atom’s 4s sublevel has

to atom’s 4s sublevel has

lower energy than five orbitals

lower energy than five orbitals

related to 3d sublevel)

related to 3d sublevel)

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48

1s

2s 2p

3s 3p 3d

4s 4p 4d 4f

5s 5p 5d 5f

6s 6p 6d 6f

7s 7p 7d 7f

Pauli e

xcl

usi

on

Pauli e

xcl

usi

on

pri

nci

ple

pri

nci

ple

-ato

mic

-a

tom

ic

orb

ital h

as

at

most

2

orb

ital h

as

at

most

2

ele

ctro

ns

ele

ctro

ns

No more than 2

No more than 2 electrons, each with

electrons, each with opposing spin (

opposing spin (↾⇂↾⇂), ), can be located in

can be located in energy level

energy levelNo two electrons can

No two electrons can

have the same set of

have the same set of

quantum numbers

quantum numbersIf 1 energy level is

If 1 energy level is available, then 2

available, then 2 electrons can be

electrons can be accommodated

accommodated

04/10/23

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04/10/23 50

n l m Subshell

notation

# orbitals in

subshell

# electrons needed to fill

subshell

Total # electrons

in subshell

1 0 0 1s 1 2 (± ½) 2

2 0 0 2s 1 2

2 1 -1,0,1 2p 3 6 8

3 0 0 3s 1 2

3 1 -1,0,1 3p 3 6

3 2 -2,-1,0,1,2 3d 5 10 18

4 0 0 4s 1 2

4 1 -1,0,1 4p 3 6

4 2 -2,-1,0,1,2 4d 5 10

4 3 -3,-2,-1,0,1,2,3

4f 7 14 32

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RIGHTWRONG

Hund’s ruleHund’s rule: Orbitals of equal energy are each occupied by one electron before any orbital is occupied by 2nd electron, and all electrons in singly occupied orbitals must have same spin

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Exceptions to electron configuration Exceptions to electron configuration rulesrules

Half filled 4s and 3d is more stable Half filled 4s and 3d is more stable than expected electron configuration than expected electron configuration

1

expected

observed

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Ele

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Ele

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Confi

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of

Confi

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Ions

Ions

1. Which of the following sets of

1. Which of the following sets of

atomic number and configuration

atomic number and configuration

represent the ground state

represent the ground state

electron configuration of an atom

electron configuration of an atom

or ion? State which atom or ion it

or ion? State which atom or ion it

is. is.        a)   A = 8,  1

       a)   A = 8,  1ss 22 2 2ss 22 2 2pp 44

       b)   A = 11,  1

       b)   A = 11,  1ss 22 2 2ss 22 2 2pp 66

       c)   A = 14,  1

       c)   A = 14,  1ss 22 2 2ss 22 2 2pp 66 3 3ss 22

       d)   A = 22,  1

       d)   A = 22,  1ss 22 2 2ss 22 2 2pp 66 3 3ss 22

33pp 66 4 4ss 22 2. Write the correct electron

2. Write the correct electron

configurations for:

configurations for:        a)  Pb       a)  Pb 4+4+        b)  S       b)  S 2-2-        c)  Fe       c)  Fe 3+3+        d)  Zn       d)  Zn 2+2+

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3. Give the electron configurations for the following transition 3. Give the electron configurations for the following transition metal ions: metal ions:        a)  Sc       a)  Sc3+3+        b)  Cr       b)  Cr2+2+        c)  Ag       c)  Ag1+1+        d)  Ni       d)  Ni3+3+

4. Of the following species (Sc4. Of the following species (Sc00, Ca, Ca2+2+, Cl, Cl00, S, S2-2-, Ti, Ti3+3+), which are ), which are isoelectric? isoelectric?

5. Identify the group containing the element composed of atoms 5. Identify the group containing the element composed of atoms whose last electron: whose last electron:         a)  enters and fills and 's' subshell.         a)  enters and fills and 's' subshell.         b)  enters but does not fill an 's' subshell.         b)  enters but does not fill an 's' subshell.         c)  is the first to enter a 'p' subshell.         c)  is the first to enter a 'p' subshell.         d)  is the next to the last in a given 'p' subshell.         d)  is the next to the last in a given 'p' subshell.         e)  enters and fills a given 'p' subshell.         e)  enters and fills a given 'p' subshell.         f)   is the first to enter a 's' subshell.         f)   is the first to enter a 's' subshell.         g)  half fills a 'd' subshell.         g)  half fills a 'd' subshell.

6. Write the electron configuration for argon. Name two positive 6. Write the electron configuration for argon. Name two positive and two negative ions that have this configuration.and two negative ions that have this configuration.

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1. a)   oxygen as a neutral atom 1. a)   oxygen as a neutral atom     b)   lithium as a +1 ion     b)   lithium as a +1 ion     c)   silicon as a +2 ion     c)   silicon as a +2 ion     d)   titanium as a +2 ion     d)   titanium as a +2 ion

2. a)  Pb2. a)  Pb4+4+   1s   1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66 4s 4s22 3d 3d1010 4p 4p66 5s 5s22 4d 4d1010 5p 5p66 6s 6s22 4f 4f1414 5d 5d88     b)  S    b)  S2-2-      1s      1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66     c)  Fe    c)  Fe3+3+    1s    1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66 4s 4s22 3d 3d33     d)  Zn    d)  Zn2+2+    1s    1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66 4s 4s22 3d 3d88

3. a)  Sc3. a)  Sc3+3+    1s    1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66     b)  Cr    b)  Cr2+2+    1s    1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66 4s 4s22 3d 3d22     c)  Ag    c)  Ag1+1+    1s    1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66 4s 4s22 3d 3d1010 4p 4p66 5s 5s00 4d 4d1010     d)  Ni    d)  Ni3+3+    1s    1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66 4s 4s22 3d 3d55

4. Ca4. Ca2+2+and  Sand  S2-2-have the same electronic configuration with 18 have the same electronic configuration with 18 electrons each. electrons each.

5.  a)  The alkali earth metals 5.  a)  The alkali earth metals      b)  The alkali metals      b)  The alkali metals      c)  The boron group      c)  The boron group      d)  The halogens      d)  The halogens      e)  The noble gases      e)  The noble gases      f)   The alkali metals      f)   The alkali metals      g)  The manganese group      g)  The manganese group

6.  1s6.  1s22 2s 2s22 2p 2p66 3s 3s22 3p 3p66 4s 4s22   = Ar = S   = Ar = S-2-2, Cl, Cl-1-1, K, K+1+1 and Ca and Ca+2+2

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Hom

ew

ork

Hom

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::

Read 5.3, pp. 135-144

Read 5.3, pp. 135-144Q pg. 141, #25, 27

Q pg. 141, #25, 27Q pp. 146-147, #60, 64,

Q pp. 146-147, #60, 64,

78 a/d, 79 a-d, 80 a/c/f

78 a/d, 79 a-d, 80 a/c/f

Test practice, pg. 149, all

Test practice, pg. 149, all

questionsquestionsUse link for quiz and

Use link for quiz and submit as before.

submit as before.http://http://

www.glencoe.com/qe/

www.glencoe.com/qe/

science.php?qi=520

science.php?qi=520

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