Transcript Classroom Rules - chemistryworkshopjr

Inorganic Chemistry
Duward Shriver
and
Peter Atkins
Dr. S. M. Condren
Dr. S. M. Condren
Dr. S. M. Condren
Dr. S. M. Condren
CHEM422 Lab
• Wednesday
• Friday
• Other
Dr. S. M. Condren
Dr. S. M. Condren
Periodic Table Exam
• Write chemical symbol for first 36 elements
in proper location on blank periodic table
• Worth 40 points total
• Up to 36 for elements 1-36
• No more than 4 points for other elements
• First attempt during week of Feb. 10.
• Part of 400 total points for “Homework”
Dr. S. M. Condren
Chapter 1
Atomic Structure
Dr. S. M. Condren
Structure of the Atom
Composed of: protons
found in nucleus
• protons
relative charge of +1
relative mass of 1.0073 amu
• neutrons
neutrons
• electrons
found in nucleus
neutral charge
relative mass of 1.0087 amu
electrons
found in electron cloud
relative charge of -1
relative mass of 0.00055 amu
Dr. S. M. Condren
Atomic Number, Mass Number, & Isotopes
• Atomic number, Z
Nuclear Notation
– the number of protons in the nucleus
– the number of electrons in a neutral atom
A
– the integer on the periodic table for each element
E
Z
• Mass Number, A
– integer representing the approximate mass of an atom
– equal to the sum of the number of protons and neutrons in the
nucleus
• Isotopes
– atoms of the same element which differ in the number of neutrons in the
nucleus
– designated by mass number
Dr. S. M. Condren
Isotopes vs. Allotropes
Isotopes - atoms of the same element with
different numbers of neutrons
- different compounds with the same
formula
Allotropes - different forms of an element
Carbon exhibits both
• Isotopes: C-12
C-13
C-14
• Allotropes: graphite, diamond, and
fullerenes
Dr. S. M. Condren
Big-Bang
• starts with universe as a singularity with
infinite density and temperature, only
radiation exists
• sudden expansion leads to rapid drop in
temperature and density
• nuclear particle transformations convert
most of universe’s energy to protons and
deuterons
Dr. S. M. Condren
The Origin of the Elements
• Nucleosynthesis of light elements
• Nucleosynthesis of heavy elements
Dr. S. M. Condren
Hydrogen Burning
Hydrogen Burning (fusion)
4 1H ---> 4He + 2 positrons + 2 neutrinos
+ 2.5 x 106 MJ/mol
after about 1/10 of hydrogen consumed,
changes to helium burning
Dr. S. M. Condren
Helium Burning
and Helium Reactions
Helium Burning (fusion)
3 4He ----> 12C
Helium Reactions
12C + 4He ---> 16O
16O + 4He ---> 20Ne
20Ne + 4He ---> 24Mg
when temperature reaches 5 x 108 K, carbon fusion
Dr. S. M. Condren
Carbon Burning
2 12C ---> 23Na + 1H
2 12C ---> 20Ne + 4He
etc.
Dr. S. M. Condren
Neutron Capture
68Zn
+ 1n --->
80Br + 1n --->
69Zn*
--->
81Br* --->
etc.
Dr. S. M. Condren
+ b
81Kr + b
69Ga
Average Binding Energy per Nucleon
Dr. S. M. Condren
Relative Penetrating Powers of Radiation
Dr. S. M. Condren
Decay Scheme for Uranium Series
Dr. S. M. Condren
Classification of the Elements
Metals
• Lustrous, malleable, ductile, electrically
conducting solids at room temperature
Nonmetals
• Often gases, liquids, or solids that do not conduct
electricity appreciably
Metalloids
• Elements, alloys or compounds that possess some
of the characteristics of metals and some of
nonmetals
Dr. S. M. Condren
Classification of the Elements
• Metallic elements combine with nonmetallic
elements to give compounds that are typically
hard, non-volatile solids
• When combined with each other, the nonmetals
often form volatile molecular compounds
• When metals combine (or simply mix together)
they produce alloys that have most of the physical
characteristics of metals
Dr. S. M. Condren
Development of Periodic Table
Dmitri Mendeleev - Russian
1869 - Periodic Law - allowed him to
predict properties of
unknown elements
Dr. S. M. Condren
Missing elements: 44, 68, 72, & 100 amu
Dr. S. M. Condren
Dr. S. M. Condren
C&EN COVER STORY:
Dec. 20, 2004
Organometallic and Inorganic Chemistry
A stable compound containing a silicon-silicon triple bond.
Zinc-Zinc Bond
Sekiguchi A, Kinjo R, Ichinohe M.
Department of Chemistry, Graduate School of Pure and
Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki
305-8571, Japan. [email protected]
The reaction of 2,2,3,3-tetrabromo-1,1,4,4tetrakis[bis(trimethylsilyl)methyl]-1,4-diisopropyltetrasilane
with four equivalents of potassium graphite (KC8) in
tetrahydrofuran produces 1,1,4,4tetrakis[bis(trimethylsilyl)methyl]-1,4-diisopropyl-2tetrasilyne, a stable compound with a silicon-silicon triple
bond, which can be isolated as emerald green crystals stable
up to 100 degrees C in the absence of air. The SiSi triple-bond
length (and its estimated standard deviation) is 2.0622(9)
angstroms, which shows half the magnitude of the bond
shortening of alkynes compared with that of alkenes. Unlike
alkynes, the substituents at the SiSi group are not arranged in a
linear fashion, but are trans-bent with a bond angle of
137.44(4) degrees.
Dr. S. M. Condren
Decamethyldizincocene,
synthesized by Carmona and
coworkers, is the first stable
molecule with a bond between
two zinc atoms (green).
Hydrogens are not shown.
Periodic
Table
of the
Periodic
Table
of
the
Elements
Elements
IA
1
1
3
4
5
6
7
III B
IV B
VB
VI B
VII B
VIII B
IB
II B
III A
IV A
VA
VI A
VII A
1
VIII A
2
H
H
He
1.008
1.008
4.0026
10
3
2
II A
4
5
6
7
8
9
Li
Be
B
C
N
O
F
Ne
6.939
9.0122
10.811
12.011
14.007
15.999
18.998
20.183
11
12
13
14
15
16
17
18
Na
Mg
Al
Si
P
S
Cl
Ar
22.99
24.312
26.982
28.086
30.974
32.064
35.453
39.948
19
20
31
32
33
34
35
36
21
22
23
24
25
26
27
28
29
30
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
As
Se
39.102
40.08
44.956
47.89
50.942
51.996
54.938
55.847
58.932
58.71
63.54
65.37
69.72
72.59
74.922
78.96
Br
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
Rb
Sr
Y
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Sb
Te
I
Xe
85.468
87.62
88.906
91.224
92.906
95.94
* 98
101.07
102.91
106.42
107.9
112.41
114.82
118.71
121.75
127.61
126.9
131.29
55
56
57
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
79.909
Kr
83.8
Cs
Ba
**La
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
At
Rn
132.91
137.33
138.91
178.49
180.95
183.85
186.21
190.2
192.22
195.08
196.97
200.29
204.38
207.2
208.98
* 209
* 210
* 222
87
88
89
104
105
106
107
108
109
110
111
112
113
114
115
116
Rf
Ha
Sg
Ns
Hs
Mt
* 261
* 262
* 263
* 262
* 265
* 268
Fr
* 223
Ra ***Ac
226.03 227.03
58
* Designates that **Lanthanum
all isotopes are
Series
radioactive
*** Actinium
Series
59
60
61
62
Uun Uuu Uub
* 269
* 272
63
64
* 277
65
Uut
118
Uuq Uup Uuh
Uuo
*284
*285
*288
*292
Based on symbols used by ACS
66
67
68
69
S.M.Condren 2007
*294
70
71
Ce
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
140.12
140.91
144.24
* 145
150.36
151.96
157.25
158.93
162.51
164.93
167.26
168.93
173.04
174.97
90
91
92
93
94
95
96
97
98
99
100
101
102
103
Th
Pa
U
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr
232.04
231.04
238.03
237.05
* 244
* 243
* 247
* 247
* 251
* 252
* 257
* 258
* 259
* 260
Dr. S. M. Condren
Dr. S. M. Condren
Quantum Mechanics:
Wave Nature of Electrons
Atomic Force Microscope
Crommie, Lutz & Eigler
http://www.almaden.ibm.com/vis/stm/corral.html
Dr. S. M. Condren
Dr. S. M. Condren
Developed in collaboration with the
Institute for Chemical Education and the
Magnetic Microscopy Center
University of Minnesota
http://www.physics.umn.edu/groups/mmc/
Dr. S. M. Condren
http://mrsec.wisc.edu/
http://mrsec.wisc.edu/
Sample
http://www.nsf.gov/mps/dmr/mrsec.htm
http://www.nsf.gov/mps/dmr/mrsec.htm
Probe
Pull Probe Strip
Dr. S. M. Condren
Pull Probe Strip
Which best represents the poles?
(a)
(b)
(c)
North
South
Dr. S. M. Condren
Quantum Numbers
n => principal quantum number, quantized
energy levels, which energy level
n = 1, 2, 3, 4, 5, 6, 7, etc.
Dr. S. M. Condren
Quantum Numbers
l => secondary quantum number, quantized
orbital angular momentum, which sublevel
or type of orbital
s type orbital l = 0
p type orbital l = 1
d type orbital l = 2
f type orbital l = 3
g type orbital l = 4
Dr. S. M. Condren
Quantum Numbers
m => magnetic quantum number, quantized
orientation of angular momentum, which
orbital within sublevel
s type orbital
m=0
p type orbital
m = +1, 0 or -1
one value for each of the three p orbitals
d type orbital
m = +2, +1, 0, -1 or -2
one value for each of the five d orbitals
f type orbital
m = +3, +2, +1, 0, -1, -2 or -3
one value for each of the seven f orbitals
Dr. S. M. Condren
Hydrogenic Energy Levels
hcZ2R
E = - ----------n2
where n = 1, 2, 3, hhh
R = Rydberg constant
mce4
R = ----------- = 13.6 eV
8h3ceo2
Dr. S. M. Condren
s- and p-orbitals
Dr. S. M. Condren
d-orbitals
Dr. S. M. Condren
f-orbitals
Dr. S. M. Condren
Many Electron Atoms
• Electronic Configuration
• Pauli exclusion principle
– No more than 2 electrons can occupy a single
orbital
– No two electrons can have the exact same four
quantum numbers
Dr. S. M. Condren
Electron Filling Order Diagram
Start here
1s
2s
3s
4s
5s
6s
7s
2p
3p
4p
5p
6p
7p
3d
4d 4f
5d 5f
6d
Dr. S. M. Condren
Ground state electronic configurations
Dr. S. M. Condren
Electronic Configuration
As atom
33 electons
1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10, 4p3
or
[Ar] 4s2, 3d10, 4p3
Dr. S. M. Condren
Mn: [Ar]4s2 3d?
How many d electrons does Mn have?
4, 5, 6
Dr. S. M. Condren
Electronic Configuration
negative ions
add electron(s), 1 electron for each negative
charge
S-2 ion
(16 + 2) electrons
1s2, 2s2, 2p6, 3s2, 3p6
Dr. S. M. Condren
Electronic Configuration
positive ions
remove electron(s), 1 electron for each positive charge
Electrons are first removed from orbital with highest n
&l
Mg+2 ion
(12-2) electrons
1s2, 2s2, 2p6
Fe atom
Fe+2 ion
(26) electrons
(26-2) electrons
[Ar]4s23d6
[Ar]4s03d6
Dr. S. M. Condren
How many valence electrons are in Cl,
[Ne]3s2 3p5?
2, 5, 7
Dr. S. M. Condren
Shielding
Z* => effective nuclear charge
Z* = Z - S
S => shielding as defined by Slater’s Rules
http://en.wikipedia.org/wiki/Slater's_rules
Dr. S. M. Condren
Slater's Rules for Calculating Shielding
1. for [ns, np] electrons (e-s), e-s to the right in the
modified electronic configuration contribute
nothing
2. for [ns, np] e-s, other electrons of same group
contribute 0.35 each (except 1s, 0.3)
3. each electron in n - 1 group, contribute 0.85
4. each electron in n - 2 group, contribute 1.0
5. nd & nf group, rules 1 & 2 remain the same, all
electrons to the left contribute 1.0
modified electronic configuration
[1s][2s2p][3s3p][3d][4s] etc
Dr. S. M. Condren
Examples: for the 4 s electron in Cu atom
[1s2][2s22p6][3s23p6][3d10][4s1]
n - 2 group => 10 * 1.0
n - 1 group => 18 * 0.85
n group => 0 * 0.35
Z* = 29 - ((10 * 1.0) + (18 * 0.85) + (0 * 0.35))
= 29 - 10 - 15.3
= 3.7
Dr. S. M. Condren
Example: for a 3 d electron in Cu atom
[1s2][2s22p6][3s23p6][3d10][4s1]
rule 5. group
18 * 1.0
9 other d electrons * 0.35
Z* = 29 - ((18 * 1.0) + (9 * 0.35))
= 29 - 18 - 3.2
= 7.8
Dr. S. M. Condren
Effective Nuclear Charge
Name
Z
hydrogen
helium
lithium
beryllium
boron
carbon
nitrogen
oxygen
fluorine
neon
sodium
magnesium
aluminum
silicon
phosphorus
sulfur
chlorine
argon
potassium
calcium
scandium
titanium
vanadium
chromium
manganese
iron
cobalt
nickel
copper
zinc
gallium
germanium
Effective Nuclear Charge
n-2
n-1
n
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Z*
1
2
2
2
2
2
2
2
2
10
10
10
10
10
10
10
10
10
10
10
10
10
10
Dr. S. M. Condren
2
2
2
2
2
2
2
2
8
8
8
8
8
8
8
8
8
8
9
10
11
13
13
14
15
16
18
18
18
18
1
2
3
4
5
6
7
1
2
3
4
5
6
7
1
1
1
1
1
1
1
1
1
2
3
1
1.7
1.3
1.95
2.6
3.25
3.9
4.55
5.2
5.85
2.2
2.85
3.5
4.15
4.8
5.45
6.1
6.75
2.2
2.85
3
3.15
3.3
2.95
3.6
3.75
3.9
4.05
3.7
4.35
5
5.65
Effective Nuclear Charge vs. Atomic Number
9
8
Effective Nuclear Charge
7
6
5
4
3
2
1
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Atomic Number
Dr. S. M. Condren
Atomic Radius
• decrease left to right across a period
– as nuclear charge increases, number of
electrons increase; however, the nucleus acts as
a unit charge while the electrons act
independently, pulling electrons towards the
nucleus, decreasing size
• increase top to bottom down a group
– each additional electron “shell” shields the
outer electrons from the nuclear charge
• increases from upper right corner to the
lower left corner
Dr. S. M. Condren
Elemental Properties vs. Atomic Number
9
8
7
6
5
Z*
4
a.
radius
3
2
1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Atomic Number
Dr. S. M. Condren
Ionic Radius
• same trends as for atomic radius
• positive ions smaller than atom
• negative ions larger than atom
Isoelectronic Series
• series of negative ions, noble gas atom, and
positive ions with the same electronic
confiuration
• size decreases as “positive charge” of the
nucleus increases
Dr. S. M. Condren
Ionization Energy
• energy necessary to remove an electron to
form a positive ion, I
• low value for metals, electrons easily
removed
• high value for non-metals, electrons
difficult to remove
• increases from lower left corner of periodic
table to the upper right corner
Dr. S. M. Condren
Ionization Energies
first ionization energy
• energy to remove first electron from an
atom
second ionization energy
• energy to remove second electron from a +1
ion
etc.
Dr. S. M. Condren
Elemental Properties vs. Atomic Number
30
25
20
Z*
15
1st I. E.
10
5
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Atomic Number
Dr. S. M. Condren
Electron Affinity
• energy released when an electron is added
to an atom
• same trends as ionization energy, increases
from lower left corner to the upper right
corner
• metals have low “Ea”
• nonmetals have high “Ea”
Dr. S. M. Condren
Elemental Properties vs. Atomic Number
30
25
20
15
Z*
1st I. E.
E.A.
10
5
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
-5
Atomic Number
Dr. S. M. Condren
Electronegativity
Pauling Scale
• relative attraction of an atom for electrons,
its own and those of other atoms
• same trends as ionization energy, increases
from lower left corner to the upper right
corner
• fluorine: E.N. = XP = 4.0
• based on the energetics of bond formation
Dr. S. M. Condren
Electronegativity
Milliken Scale
• Based on the average of the ionization
energy and electron affinity
• XM = ½(I + Ea)
Dr. S. M. Condren
Elemental Properties vs. Atomic Number
30
25
20
15
Z*
1st I. E.
E.A.
EN.
10
5
0
1 2
3 4 5
6 7 8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
-5
Atomic Number
Dr. S. M. Condren