Embed Size (px)
Citation preview
AP Notes Chapter 7AP Notes Chapter 7Electron Configuration
Magnetism
Periodic Trends
Aufbau PrincipleAufbau Principle
Aufbau is German for building up.Aufbau is German for building up. As the protons are added one by one, As the protons are added one by one,
the electrons fill up hydrogen-like the electrons fill up hydrogen-like orbitals.orbitals.
e- are added to atoms into the lowest e- are added to atoms into the lowest energy level & sub-level availableenergy level & sub-level available
Fill up in order of energy levels.Fill up in order of energy levels.
DetailsDetails Valence electronsValence electrons- the electrons in the - the electrons in the
outermost energy levels (not d).outermost energy levels (not d). Core electronsCore electrons- the inner electrons.- the inner electrons. Hund’s RuleHund’s Rule- The lowest energy - The lowest energy
configuration for an atom is the one configuration for an atom is the one that will have the maximum number that will have the maximum number of of unpaired unpaired electrons in the orbital.electrons in the orbital.
C 1sC 1s2 2 2s2s22 2p 2p22
max emax e--
n = 1n = 1
max emax e--
n = 1 s 2n = 1 s 2n = 2n = 2
max emax e--
n = 1 s 2n = 1 s 2n = 2 s 2 8 n = 2 s 2 8 p 6 p 6 n = 3n = 3
max emax e--= 2n= 2n22
n = 1 s 2n = 1 s 2n = 2 s 2 8 n = 2 s 2 8 p 6 p 6 n = 3 s 2n = 3 s 2 p 6 18 p 6 18 d 10 d 10
Pauli Exclusion PrinciplePauli Exclusion Principle nn ll mmll ss
11 00 0 0 +1/2+1/211 00 0 0 -1/2-1/222 00 0 0 +1/2+1/222 00 0 0 -1/2-1/222 11 -1 -1 +1/2+1/222 11 -1 -1 -1/2-1/2
22 11 0 0 +1/2+1/222 11 0 0 -1/2-1/2
22 11 1 1 +1/2+1/222 11 1 1 -1/2-1/2
Orbital
1S
2s
2p
Pauli Exclusion PrinciplePauli Exclusion Principle
No 2 eNo 2 e-- in same atom can in same atom can have the same set of four have the same set of four quantum numbersquantum numbers
Quantum #s___, ___, ___, ___ n ml ms
Electron ProbabilitySpace &
Quantum Numbers
Spin QN = mSpin QN = mss (s) (s)
spin of espin of e-- on own axis on own axis
2
1ms
Incr
easi
ng e
nerg
y
1s
2s
3s
4s
5s6s
7s
2p
3p
4p
5p
6p
3d
4d
5d
7p 6d
4f
5f
He with 2 electrons
Ne with 10 electrons
Ar with 18 electrons
Fill from the bottom up Fill from the bottom up following the arrowsfollowing the arrows
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2
• 2• electrons
2s2
• 4
2p6 3s2
• 12
3p6 4s2
• 20
3d10 4p6
5s2
• 38
4d10 5p6 6s2
• 56
7s 7p ...6s 6p 6d ...5s 5p 5d 5f ...4s 4p 4d 4f3s 3p 3d2s 2p1s
DetailsDetails Elements in the same column have Elements in the same column have
the same electron configuration.the same electron configuration. Put in columns because of similar Put in columns because of similar
properties.properties. Similar properties because of electron Similar properties because of electron
configuration.configuration. Noble gases have filled energy levels.Noble gases have filled energy levels. Transition metals are filling the d Transition metals are filling the d
orbitalsorbitals
ExamplesExamples33LiLi
66CC
88OO
1919KK
2424CrCr
2929CuCu
ExceptionsExceptions
Ti = [Ar] 4sTi = [Ar] 4s22 3d 3d22 V = [Ar] 4sV = [Ar] 4s22 3d 3d33
Cr = [Ar] 4sCr = [Ar] 4s11 3d 3d5 5
Mn = [Ar] 4sMn = [Ar] 4s22 3d 3d55
Half filled orbitals.Half filled orbitals. Scientists aren’t sure of why it Scientists aren’t sure of why it
happenshappens same for Cu [Ar] 4ssame for Cu [Ar] 4s11 3d 3d1010
All atoms want a noble All atoms want a noble gas or pseudo noble gas or pseudo noble gas configurationgas configuration
Atoms with full or half-fullAtoms with full or half-full
sub-levels are particularlysub-levels are particularly
stablestable
Gain or loss of eGain or loss of e-- produces ionsproduces ions
Consider: ZnConsider: Zn2+2+, Ag, Ag++, Cu, Cu2+2+
Energy Level DiagramEnergy Level Diagram
3d __ __ __ __ __3d __ __ __ __ __4s __4s __ 3p __ __ __ 3p __ __ __3s __ 3s __ 2p __ __ __ 2p __ __ __2s __2s __1s __ 1s __
Gain or loss of eGain or loss of e-- produces ionsproduces ions
Consider: ZnConsider: Zn2+2+, Ag, Ag++, Cu, Cu2+2+
Ions with full or half-full Ions with full or half-full sub-levels are particularly sub-levels are particularly
stablestable
Gain or loss of eGain or loss of e-- produces ionsproduces ions
Consider: NaConsider: Na++, Ne, F, Ne, F--
Energy Level DiagramEnergy Level Diagram
3d __ __ __ __ __3d __ __ __ __ __4s __4s __ 3p __ __ __ 3p __ __ __3s __ 3s __ 2p __ __ __ 2p __ __ __2s __2s __1s __ 1s __
Gain or loss of eGain or loss of e-- produces ionsproduces ions
Consider: NaConsider: Na++, Ne, F, Ne, F--
Chemical species with the Chemical species with the same esame e-- configuration are configuration are
ISOELECTRONICISOELECTRONIC
Diamagnetic - Slightly repelled by a strong magnet (moments counter each other e- are paired)
Paramagnetic – Attracted to magnetic field (moments not aligned e- are unpaired )
Ferromagnetic – Materials retain a magnetic field if one has been induced (moments are aligned e- are unpaired)
Trendsof the
Periodic Table
Triplet Trends Triplet Trends
Organize trends Organize trends Use only increasing properties Use only increasing properties Learn the diagonal NOT the two Learn the diagonal NOT the two
vectors that make up the diagonal….. vectors that make up the diagonal….. You can always recreate the two You can always recreate the two
vectors so you have less to learn or vectors so you have less to learn or memorizememorize
Atomic NumberAtomic Number Increases to the rightIncreases to the right Increases down Increases down
Atomic MassAtomic Mass Increases to the rightIncreases to the right Increases down Increases down
Nuclear ChargeNuclear Charge Increases to the rightIncreases to the right Increases down Increases down
Atomic RadiusAtomic Radius
Is taken as the covalent Is taken as the covalent radius for non-metallic radius for non-metallic elements and as the metallic elements and as the metallic radius for metalsradius for metals
Atomic RadiusAtomic Radius
Covalent radius is Covalent radius is one-half the one-half the distance between distance between the nuclei of two the nuclei of two identical atoms identical atoms that are singly that are singly bonded to one bonded to one another. another.
Atomic RadiusAtomic Radius Covalent radii for elements Covalent radii for elements
whose atoms do not bond whose atoms do not bond to one another can be to one another can be estimated by combining estimated by combining radii of those that do with radii of those that do with the distances between the distances between unlike atoms in various unlike atoms in various molecules.molecules.
Atomic RadiusAtomic Radius
Metallic radius is one-half Metallic radius is one-half the closest internuclear the closest internuclear distance in a metallic distance in a metallic crystal.crystal.
0
50
100
150
200
1 3 5 7 9 11 13 15 17 19
Atomic Number
Ato
mic
Rad
ius
(pm
)Atomic RadiusAtomic Radius
Atomic RadiusAtomic Radius
Ionization EnergyIonization Energy
Is the energy required to Is the energy required to remove the outermost remove the outermost electron from an atom or a electron from an atom or a positive ion in the ground positive ion in the ground state. state.
First Ionization EnergyFirst Ionization Energy
Energy required to remove Energy required to remove the first electron from a the first electron from a neutral atom.neutral atom.
0
500
1000
1500
2000
2500
1 3 5 7 9 11 13 15 17 19
Atomic Number
1st
Ion
izat
ion
En
erg
y (k
J/m
ol)
First Ionization EnergyFirst Ionization Energy
First Ionization EnergyFirst Ionization Energy
First Ionization EnergyFirst Ionization Energy
Second Ionization Second Ionization EnergyEnergy Energy needed to remove Energy needed to remove
the outermost electron from the outermost electron from a +1 ion. a +1 ion.
Energy needed to remove Energy needed to remove the second electron from a the second electron from a neutral atom.neutral atom.
0
1000
2000
3000
4000
5000
6000
7000
8000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Atomic Number
2nd
Io
niz
atio
n E
ner
gy
(kJ/
mo
l)
Second Ionization Second Ionization EnergyEnergy
Electron AffinityElectron Affinity
Energy released or Energy released or absorbed when an electron absorbed when an electron is added to the valence level is added to the valence level of a gas-phase atom.of a gas-phase atom.
-400
-350
-300
-250
-200
-150
-100
-50
0
50
100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Atomic Number
Ele
ctro
n A
ffin
ity
(kJ/
mo
l)
Electron AffinityElectron Affinity
Electron AffinityElectron Affinity
ElectronegativityElectronegativity
Ability to bond & desire for electronsAbility to bond & desire for electrons
