Download Chemical Bonds

Chemical Bonds
What is a chemical bond? Why do
chemical bonds form?
• A chemical bond is a type of attractive force
that forms between atoms.
• All atoms react to obtain a stable and full
outer electron configuration.
• Only noble gases naturally possess a stable
arrangement that includes a perfect balance
and distance between the positive protons
and negative electrons.
The Octet Rule
The Octet Rule
• All noble gases except He has an s2p6 configuration (Note:
2 + 6 = 8….”octet” means the number 8)
• Octet rule: atoms tend to gain, lose, or share electrons
until they are surrounded by 8 valence electrons (4
electron pairs).
• Caution: there are many exceptions to the octet rule. For
example; H, He Li and Be follow “duet rule.”
How do atoms achieve a full “octet?”
• Atoms will gain, lose or share electrons to
achieve a stable, completely full outer
electron shell. (called valence shell).
• The gaining or losing of valence electrons is a
CHEMICAL REACTION!!
• The difference in electronegativity values of
atoms, when placed into contact with each
other, determines the loss or gain of
electrons.
Bonding and Electronegativity
Electronegativity
• Electronegativity: The ability of one atom or group of
atoms to attract electrons to itself.
• Pauling set electronegativities on a scale from 0.7 (Cs) to
4.0 (F).
• Electronegativity increases
• across a period and
• down a group.
Electronegativities of Elements
Electronegativity
http://group.chem.iastate.edu/Greenbowe/se
ctions/projectfolder/flashfiles/reaction/bondin
g1.swf
Animation of electron transfer between
selected atoms.
Lewis Structures
-Chemical reactions involve valence electrons.
-Lewis structures are shorthand version of
atoms showing only their valence electrons.
-Why?? Only valence electrons transferred
during most chemical reactions.
Examples of Longhand and Lewis Electron Symbols
Lewis Symbols
http://www.mhhe.com/physsci/chemistry/chang7/esp/folder_structure/bo/m2/s1/i
ndex.htm
Animation of Lewis Diagrams
Chemical Bonding
Covalent Bonds
…atoms share electrons to get a full valence shell
C
1s2 2s2 2p2
(4 v.e–)
F
1s2 2s2 2p5
(7 v.e–)
both need 8 valence electrons for a full outer shell
(octet rule)
Covalent bonding
•
•
•
•
Fluorine has seven valence electrons
A second F atom also has seven
By sharing electrons
Both end with full orbitals (stable octets)
F
8 Valence
electrons
F
8 Valence
electrons
Chemical Bonding
Ionic Bonds:
atoms give up or gain electrons and are attracted
to each other by coulombic attraction
Na loses an e–
Na  Na1+ + e–
ionic compounds = salts
Cl gains an e–
Cl + e–  Cl1–
Na1+ + Cl1–  NaCl
K1+ + NO31–  KNO3
where NO31– is a polyatomic ion: a charged group of atoms
that stay together
Ionic Bonding
NaCl
n=3
-
n=2
n=3
-
-
-
-
-
-
-
Na
[Ne]3s1
-
-
-
+
-
-
-
-
-
-
-
-
-
Cl
[Ne]3s23p5
-
-
-
Na+
[Ne]
-
-
-
Cl[Ne]3s23p6
Transfer of electrons to achieve a stable octet (8 electrons in valence shell).
sodium metal
2 Na
and
chlorine gas
+ Cl2
Copyright © 2007 Pearson Benjamin Cummings. All rights reserved.
react to form
sodium chloride
2 NaCl
Covalent Bonding
n=2
-
-
-
-
n=1
-
-
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
-
O
[He]2s22p4
-
O
[He]2s22p4
O2
Sharing of electrons to achieve a stable octet (8 electrons in valence shell).
Properties of Salts
VERY HARD
each ion is bonded to several oppositelycharged ions
HIGH MELTING POINTS
many bonds must be broken
BRITTLE
with sufficient force, like atoms are brought
next to each other and repel
Vocabulary
• Chemical Bond
– attractive force between atoms or ions that binds
them together as a unit
– bonds form in order to…
• decrease potential energy (PE)
• increase stability
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
Vocabulary
CHEMICAL FORMULA
IONIC
COVALENT
formula
unit
molecular
formula
NaCl
CO2
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
Vocabulary
COMPOUND
2 elements
binary
compound
NaCl
more than 2
elements
ternary
compound
NaNO3
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
Vocabulary
ION
1 atom
2 or more atoms
monatomic
Ion
polyatomic
Ion
+
Na
NO3
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
-
Types of Bonds
COVALENT
IONIC
Bond
Formation
e- are transferred from metal
to nonmetal
e- are shared between two
nonmetals
Type of
Structure
crystal lattice
true molecules
Physical
State
solid
liquid or gas
Melting
Point
high
low
Solubility in
Water
yes
usually not
Electrical
Conductivity
yes
(solution
or liquid)
Other
Properties
no
odorous
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
Types of Bonds
METALLIC
bond formation
type of structure
physical state
electrons are delocalized
among metal atoms
“electron sea”
solid
very high
melting point
no
solubility in water
yes
conductivity
other properties
(any form)
malleable, ductile, lustrous
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
Types of Bonds
Ionic Bonding - Crystal Lattice
Table salt
Types of Bonds
Ionic Bonding - Crystal Lattice
Table salt
Types of Bonds
Covalent Bonding - True Molecules
Nitrogen
Water
Ammonia
Diatomic
Molecule
Lewis Structure
Lewis structure:
a model of a covalent molecule that
shows all of the valence electrons
1. Two shared electrons make a single covalent bond,
four make a double bond, etc.
2. unshared pairs: pairs of un-bonded valence electrons
3. Each atom needs a full outer shell, i.e., 8 electrons.
Exception: H needs 2 electrons
Lewis Structure
carbon tetrafluoride (CF4)
x
x
x
x
o
o
x
x
x
C
o
o
x
x
x
F
x
x
x
x
x
x
F
x
x
x
x
x
o
o
F
x
C
x
x
o
ox
x
x
x
x
x
F
x
x
x
F
x
x
x
x
F
x
x
x
x
x
x
x
F
x
C
F
x
x
x
x
x
x
x
x
x
F
x
covalent compounds = molecular compounds
(have lower melting points than do ionic compounds)
x
x
x
x
Lewis Structure
o
H
x o
x
o
H oCx H
H
x
o
methane (CH4)
Co
o
H
o o
x x
o
nitrogen triiodide (NI3)
N
o
x
x
o
x x
x
x
x
I
x x
I
o o
o
x
x x
x
x
o
carbon dioxide (CO2)
o
Co
o
x x
x
x
x x
x
Ox
H
H C H
H
o
x
x
x
Nx xIx
o
x
x
I
x x
o
x
Ox
x x
x
o
o
Ox
x
x
o o
I
x x
x
x
x x
x
Co
o
x x
x
x
xx
x
x
x x
N xIx
x
x
I
x x
x
x
xx
O
xx = C = O
xx
Properties of Metals
conduct heat and electricity; ductile; malleable
Other Types of Bonds
dipole-dipole forces
hydrogen bonds
London dispersion forces
ion-dipole forces (solutions)
Writing Formulas of Ionic Compounds
chemical formula:
has neutral charge;
shows types of atoms and how many of each
To write an ionic compound’s formula, we need:
1. the two types of ions
2. the charge on each ion
Na1+
and
F1–
NaF
sodium fluoride
Ba2+
and
O2–
BaO
barium oxide
Na1+
and
O2–
Na2O
sodium oxide
Ba2+
and
F1–
BaF2
barium fluoride
Ca2+
and
P3–
Ca3P2
calcium phosphide
2+
Ca
Ca2+
2+
3Ca
P
Ca
3 2P
Formula Unit
2+
Ca
P3Ca2+
P 3-
3P
Ca2+
Criss-Cross Rule
criss-cross rule:
charge on cation / anion
“becomes” subscript of anion / cation
** Warning: Reduce to lowest terms.
Al3+ and O2–
Ba2+ and S2–
In3+ and Br1–
In1 Br3
Al2 O3
Ba2 S2
Al2O3
BaS
InBr3
aluminum oxide
barium sulfide
indium bromide
Writing Formulas w/Polyatomic Ions
Parentheses are required only when you need more
than one “bunch” of a particular polyatomic ion.
?
Ba2+
and
SO42–
BaSO4
barium sulfate
Mg2+
and
NO21–
Mg(NO2)2
magnesium nitrite
NH41+
and
ClO31–
NH4ClO3
ammonium chlorate
Sn4+
and
SO42–
Sn(SO4)2
tin (IV) sulfate
Fe3+
and
Cr2O72–
Fe2(Cr2O7)3
iron (III) dichromate
NH41+
and
N3–
(NH4)3N
ammonium nitride
Compounds Containing Polyatomic Ions
Insert name of ion where it should go in the compound’s name.
Write formulas:
iron (III) nitrate
ammonium phosphide
ammonium chlorite
zinc phosphate
lead (II) permanganate
Fe3+
3 NO31–
Fe(NO3)3
3 NH41+
P3–
(NH4)3P
ClO21–
NH4ClO2
NH41+
3 Zn2+
Pb2+
2 PO43–
Zn3(PO4)2
2 MnO41–
Pb(MnO4)2
Writing Formulas of Ionic Compounds
Write names:
(NH4)2S2O3
ammonium thiosulfate
AgBrO3
silver bromate
(NH4)3N
ammonium nitride
U(CrO4)3
U?6+
Cr2(SO3)3
2 Cr ?3+
3 CrO42–
3 SO32–
uranium (VI) chromate
chromium (III) sulfite
Writing Formulas of Covalent Molecules
 Covalent Molecules
contain two types of nonmetals
Key: FORGET CHARGES
What to do:
Use Greek prefixes to indicate how many atoms
of each element, but don’t use “mono” on first element.
1 – mono
2 – di
3 – tri
4 – tetra
6 – hexa
7 – hepta
8 – octa
9 – nona
5 – penta
10 – deca
Writing Formulas of Covalent Molecules
EXAMPLES:
carbon dioxide
CO
dinitrogen trioxide
N2O5
carbon tetrachloride
NI3
CO2
carbon monoxide
N2O3
dinitrogen pentoxide
CCl4
nitrogen triiodide
Multiple-Charge Cations with Elemental Anions
Pb2+/Pb4+,
Sn2+/Sn4+,
transition elements (not Ag or Zn)
A. To name, given the formula:
1. Figure out charge on cation.
2. Write name of cation.
Stock System
3. Write Roman numerals in ( )
to show cation’s charge.
4. Write name of anion.
FeO
Fe?2+
of nomenclature
O2–
iron (II) oxide
Fe2O3
?
2 Fe3+
3 O2–
iron (III) oxide
CuBr
?
Cu1+
Br1–
copper (I) bromide
CuBr2
Cu?2+
2 Br1–
copper (II) bromide
B. To find the formula, given the name:
1. Write symbols for the two types of ions.
2. Balance charges to write formula.
cobalt (III) chloride
Co3+ Cl1–
CoCl3
tin (IV) oxide
Sn4+ O2–
SnO2
tin (II) oxide
Sn2+ O2–
SnO
Traditional (OLD) System of Nomenclature
…used historically (and still some today) to name
compounds w/multiple-charge cations
To use:
1. Use Latin root of cation.
2. Use -ic ending for higher charge; (“icky” food is good for you!)
“ -ous “
“ lower “ ; (“delicious” food is not good for you!)
3. Then say name of anion, as usual.
Element
Latin root
-ic
-ous
gold, Au
aur-
Au3+
Au1+
lead, Pb
plumb-
Pb4+
Pb2+
tin, Sn
stann-
Sn4+
Sn2+
copper, Cu
cupr-
Cu2+
Cu1+
iron, Fe
ferr-
Fe3+
Fe2+
Write formulas:
cuprous sulfide
Cu1+ S2–
Write names:
Pb3P4
Cu2S
copper (I) sulfide
auric nitride
Au3+ N3–
lead (IV) phosphide
Pb3P2
AuN
lead (II) phosphide
SnCl4
ferrous fluoride
iron (II) fluoride
3 Pb? 2 P3–
plumbous phosphide
gold (III) nitride
Fe2+ F1–
3 Pb? 4 P3–
plumbic phosphide
FeF2
Sn? 4 Cl1–
stannic chloride
tin (IV) chloride
K1+
e-
e-
potassium atom
1BrBr
bromine atom
K
Br
e-
bromine atom
potassium atom
K1+
bromide ion
potassium
potassium
ion
bromide
potassium ion
Br1bromide ion
KBr
Br1-
K1+
Mg2+
O2Br1-
magnesium bromide
MgBr2
K1+
potassium oxide
K2O
K1+
Br1-
Al3+
N3-
PO43Pb4+
K1+
O2K1+
?
Ca2+
S2-
Br1-
OH1-
Mg2+
Cu2+
Br1-
NH41+
NO31-
OH1-
Chemical Bonding Activity
Na1+
OH1-
N3Pb4+
Al3+
N3N3-
M1+
(metal)
(metal)
M2+
(metal)
M1+
(metal)
N3-
Pb4+
N2(nonmetal)
Pb4+
N3-
Ca2+
OH1Mg2+
?
Pb4+
N3-
Pb3N4
OH1-
lead (IV) nitride
or
plumbic nitride
Pb4+
N3-
Key
http://www.unit5.org/christjs/4bondingact.doc
4.
1.
5.
N3-
K1+
Br1-
Pb4+
N3-
Al3+
KBr
N3-
2.
K1+
AlN
O2K1+
6.
OH1OH1-
Br1-
Cu(OH)2
Mg2+
Br1MgBr2
N3-
Cu2+
K2O
3.
Pb4+
7.
NH41+
Pb4+
N3-
NO31-
NH4NO3
Pb3N4
Key
8.
9.
10.
NH41+
Ca2+
O2-
PO4
NH41+
3-
PO43-
Al3+
NH41+
Ca2+
O2-
(NH4)3PO4
PO43Ca2+
Ca3(PO4)2
11.
Al3+
Fe2+
O2-
O2-
FeO
Al2O3
13.
Key
14.
S2-
Pb2+
12.
O2-
S2-
Pb4+
PbS
Fe3+
S215.
O2-
Cu2+
O2-
S2CuO
Fe3+
O2-
Pb4+
16.
Cu1+
O2-
S2Cu1+
Fe2O3
Pb
PbS
2S
24
3
Cu2O
Binary Compounds
Containing a Metal of Variable Oxidation Number
To name these compounds, give the name of the metal (Type II
cations) followed by Roman numerals in parentheses to indicate
the oxidation number of the metal, followed by the name of the
nonmetal, with its ending replaced by the suffix –ide.
Examples
Stock System
Traditional (OLD) System
FeCl2
FeCl3
Iron (II) chloride
Iron (III)chloride
Ferrous chloride
Ferric chloride
SnO
SnO2
Tin (II)oxide
Tin (IV) oxide
Stannous oxide
Stannic oxide
(“ic” ending = higher oxidation state;
“ous” is lower oxidation state)
Type II Cations
Common Type II Cations
Ion
Stock System
Fe 3+
iron (III)
Fe 2+ iron (II)
Cu 2+ copper (II)
Cu 1+ copper (I)
Co 3+ cobalt (III)
Co 2+ cobalt (II)
Sn 4+ tin (IV)
Sn 2+ tin (II)
Pb 4+ lead (IV)
plumbic
Pb 2+ lead (II)
Hg 2+ mercury (II)
Hg2 2+
mercury (I)
Traditional System
ferric
ferrous
cupric
cuprous
cobaltic
cobaltous
stannic
stannous
plumbous
mercuric
mercurous
*Mercury (I) ions are always bound together in pairs to form Hg2 2+
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 90
Naming Binary Compounds
Formula
Name
1
Hg2O
mercury (I) oxide
____________________
2
HgO
mercury (II) oxide
____________________
CuF2
3 ________________
copper (II) fluoride
Cu2S
4 ________________
copper (I) sulfide
5
Cr2O3
PbO2
6 ________________
chromium (III) oxide
____________________
lead (IV) oxide
Periodic
Table
with
charges
Single-charge cations
Multiple-charge cations
Elemental anions
1+
1
H
2+
3+
Li
Be
B
3
4
1
2
3
Na Mg
11
4
K
19
5
7
Ca Sc
C
N
O
F
Ne
5
6
7
8
9
10
Al
Si
P
S
Cl
Ar
13
14
15
16
17
18
Ti
V
Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br
Kr
23
24
35
36
I
Xe
53
54
Rb Sr
Y
Zr Nb Mo Tc Ru Rh Pd Ag Cd
In
39
40
41
42
49
Hf
Ta
W
72
73
74
55
56
Fr
Ra
87
88
*
W
2
1-
22
Cs Ba
1
2-
21
38
He
3-
20
37
6
1+ 2+
12
H
25
43
26
44
Re Os
75
76
27
28
29
47
30
45
46
Ir
Pt Au Hg
Tl
77
78
81
79
48
31
80
32
33
34
Sn Sb Te
50
51
Pb Bi
82
83
52
Po At Rn
84
85
86
Rf Db Sg Bh Hs Mt
104
105
106
107
108
109
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
57
58
59
Ac Th Pa
89
90
91
60
U
92
61
62
63
64
65
66
Np Pu Am Cm Bk Cf
93
94
95
96
97
98
67
68
69
70
71
Es Fm Md No Lr
99
100
101
102
103
Binary Compounds
Containing Two Nonmetals
To name these compounds, give the name of the less electronegative
element first with the Greek prefix indicating the number of atoms of that
element present, followed by the name of the more electronegative nonmetal with the Greek prefix indicating the number of atoms of that element
present and with its ending replaced by the suffix –ide.
Prefixes you should know:
Mono
Di
Tri
Tetra
1
2
3
4
Penta
5
Hexa
Hepta
Octa
Nona
Deca
6
7
8
9
10
Binary Compounds
Containing Two Nonmetals (Type III Compounds)
As2S3
1. ________________
diarsenic trisulfide
SO2
2. ________________
sulfur dioxide
P2O5
diphosphorus pentoxide
____________________
CO2
4. ________________
carbon dioxide
3.
5.
N2O5
dinitrogen pentoxide
____________________
6.
H2O
dihydrogen monoxide
____________________
Prefixes – Binaryfor
Molecular
Compounds
Greek Prefixes
Two
Nonmetals
Number Indicated
1
2
3
4
5
6
7
8
9
10
Prefixes
monoditritetrapentahexaheptaoctanonadeca-
Binary Molecular Compounds
N2O
N2O3
N2O5
dinitrogen monoxide
dinitrogen trioxide
dinitrogen pentoxide
ICl
ICl3
iodine monochloride
iodine trichloride
SO2
SO3
sulfur dioxide
sulfur trioxide
Naming Binary Compounds
Binary Compound?
Yes
Metal Present?
No
Type III
Use Greek
Prefixes
Yes
Does the metal form
more than one cation?
No
Type I
Use the element
name for the cation.
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 98
Yes
Type II
Determine the charge
of the cation; use a Roman
numeral after the cation
name.
Ternary Compounds
Ternary compounds are those containing three different elements.
(NaNO3, NH4Cl, etc.). The naming of ternary compounds involves the
memorization of several positive and negative polyatomic ions, (two or
more atoms per ion), and adding these names to the element with which
they combine.
i.e., Sodium ion, Na1+ added to the nitrate ion, NO31-, to give
the compound, NaNO3, sodium nitrate.
Binary rules for indicating the oxidation number of metals and for indicating
the numbers of atoms present are followed. The polyatomic ions that should
be learned are listed in a separate handout.
Phosphate
(PO
PO43)33- = 31 P @ 5+
5+
4 O @ 2- = 8113-
?

Fluorine and oxygen are highly electronegative and will attract
electrons very strongly. Generally, phosphorus will be 3- oxidation
state: however, when combining with oxygen, phosphorus will lose
five electrons and take on a 5+ oxidation charge.
Polyatomic Ions - Memorize
Eight “-ATE’s”
PO43SO4
……………
2- ……………
CO32ClO3
NO3
…………..
1- …………..
1- ………..….
phosphate
phosphATE
Exceptions:
sulfate
sulfATE
carbonate
carbonATE
chlorate
chlorATE
nitrate
nitrATE
NH41+
…………… ammonium
OH1-
……………
hydroxide
CN1-
…………..
cyanide
Pattern to Memorizing Nomenclature
XY
“-ide”
XYO4
“per___-ate”
1 more oxygen
XYO3
“-ate”
normal
XYO2 XYO
“-ite”
1 less oxygen
“hypo___-ite”
2 less oxygen
Polyatomic Ion:
a group of atoms that stay together and have a single, overall charge.
BrO41-
Perbromate ion
CO42ClO41IO41NO41-
PO53SO521 more oxygen
BrO31-
BrO1-
Bromate ion
BrO21-
Bromite ion
CO32-
CO22-
CO2-
ClO31-
ClO21-
ClO1-
IO31-
IO21-
IO1-
NO31-
NO21-
NO1-
PO43-
PO33-
PO23-
SO42-
SO32-
SO22-
“normal”
1 less oxygen
Carbonate ion
Chlorate ion
Iodate ion
Nitrate ion
Phosphate ion
Sulfate ion
Hypobromite ion
2 less oxygen
Polyatomic Ion:
a group of atoms that stay together and have a single, overall charge.
BrO41-
Perbromate ion
CO42ClO41IO41NO41-
PO53SO521 more oxygen
BrO31-
BrO1-
Bromate ion
BrO21-
Bromite ion
CO32-
CO22-
CO2-
ClO31-
ClO21-
ClO1-
IO31-
IO21-
IO1-
NO31-
NO21-
NO1-
PO43-
PO33-
PO23-
SO42-
SO32-
SO22-
“normal”
1 less oxygen
Carbonate ion
Chlorate ion
Iodate ion
Nitrate ion
Phosphate ion
Sulfate ion
Hypobromite ion
2 less oxygen
Ternary Compounds
NaNO2
sodium nitrite
KClO3
potassium chlorate
Ca3(PO4)2
calcium phosphate
Fe(OH)3
iron (III) hydroxide
NaHCO3
sodium bicarbonate
‘sodium hydrogen carbonate’
Calcium hydroxide
ide
Ca2+
OH1-
CaOH2
Ca - O
H
H
vs.
Ca(OH)2
HO - Ca - OH
Common Polyatomic Ions
Names of Common Polyatomic Ions
Ion
Name
Ion
Name
NH4 1+
NO2 1NO3 1SO3 2SO4 2HSO4 1-
ammonium
nitrite
nitrate
sulfite
sulfate
hydrogen sulfate
(“bisulfate” is a widely
used common name)
hydroxide
cyanide
phosphate
hydrogen phosphate
dihydrogen phosphate
CO3 2HCO3 1-
carbonate
hydrogen carbonate
(“bicarbonate” is a widely
used common name)
hypochlorite
chlorite
chlorate
perchlorate
acetate
permanganate
dichromate
chromate
peroxide
OH 1CN 1PO4 3HPO4 2H2PO4 1-
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 100
ClO 1ClO2 1ClO3 1ClO4 1C2H3O2 2MnO4 1Cr2O7 2CrO4 2O2 2-
Print Version
Ternary Compounds
Ca3(PO4) 2
1. ________________
calcium phosphate
(NH4)2CO3
2. ________________
ammonium carbonate
Al2(SO4)3
3. ________________
aluminum sulfate
4.
Na2SO4
sodium sulfate
____________________
5.
LiCN
lithium cyanide
____________________
6.
Ba(ClO3)2
Cu(OH)2
7. ________________
barium chlorate
____________________
copper (II) hydroxide
Magnesium Phosphate
Step 1:
Magnesium
Step 2:
Mg2+
PO43-
Step 3:
Mg 3
(PO4) 2
Step 4:
Phosphate
Mg3(PO4)2
variable Ir2+,3+,4+,6+
Ir F
2(Cr
3 2O 7) 3
iridium (III) dichromate
fluoride
Ca S
(OH)2
calcium hydroxide
sulfide
Ti S
(CrO
2
4) 2
titanium (IV) chromate
sulfide
variable Ti3+,4+
Pt Cl
(CH
2 3COO)2
platinum (II) acetate
chloride
variable Pt2+,4+
BaBr
(BrO
2 3)2
barium bromate
bromide
fixed
Ba2+
Sr SO
3P2 4
strontium sulfate
phosphide
fixed
Sr2+
KF
CN
potassium cyanide
fluoride
fixed
K1+
Zn I(NO
2
2)2
zinc nitrite
iodide
fixed
Zn2+
Mn Cl
(ClO
4 3) 4
manganese (IV) chlorate
chloride variable Mn2,3,4,6,7+
Au PO
2O34
gold (III) phosphate
oxide
Na NO
3P 3
sodium nitrate
phosphide
fixed
Ca2+
variable Au1+,3+
fixed
Na1+
variable Ir2+,3+,4+,6+
Ir F3
iridium (III) fluoride
Ca S
calcium sulfide
Ti S2
titanium (IV) sulfide
variable Ti3+,4+
Pt Cl2
platinum (II) chloride
variable Pt2+,4+
BaBr2
barium bromide
fixed
Ba2+
Sr 3P2
strontium phosphide
fixed
Sr2+
KF
potassium fluoride
fixed
K1+
Zn I2
zinc iodide
fixed
Zn2+
Mn Cl4
manganese (IV) chloride variable Mn2,3,4,6,7+
Au 2O3
gold (III) oxide
Na 3P
sodium phosphide
fixed
Ca2+
variable Au1+,3+
fixed
Na1+
variable Ir2+,3+,4+,6+
Ir 2(Cr2O7)3
iridium (III) dichromate
Ca (OH)2
calcium hydroxide
Ti (CrO4)2
titanium (IV) chromate
variable Ti3+,4+
Pt (CH3COO)2
platinum (II) acetate
variable Pt2+,4+
Ba(BrO3)2
barium bromate
fixed
Ba2+
Sr 3SO4
strontium sulfate
fixed
Sr2+
KCN
potassium cyanide
fixed
K1+
Zn (NO2)2
zinc nitrite
fixed
Zn2+
Mn (ClO3)4
manganese (IV) chlorate variable Mn2,3,4,6,7+
Au PO4
gold (III) phosphate
Na NO3
sodium nitrate
fixed
Ca2+
variable Au1+,3+
fixed
Na1+
Two nonmetals
carbon
sulfurN
tetrabromide
dichloride
NCl
2O35
Greek prefixes
Multiple-charge cation
Everything else
rubidium
NH4ClO
barium
KIsulfate
oxide
3
vanadium
niobium (V)
Mn
Pt(IO
(II)
Schromate
2perchlorate
53)4
Roman numeral
for name only
Roman
numeral
Charge
Polyatomic ions
CrissCross
Rule
Roman
numeral
OK
Polyatomic ions OK
Where would you file this?
VCrO4
dinitrogen pentoxide
BaO
platinum (IV) iodate
CBr4
ammonium chlorate
Nb(ClO4)5
potassium iodide
SCl2
nitrogen trichloride
Rb2SO4
manganese (V) sulfide
Two nonmetals
Greek prefixes
Multiple-charge cation
Everything else
Roman numeral
for name only
Roman
numeral
Charge
Polyatomic ions
CrissCross
Rule
Roman
numeral
OK
Polyatomic ions
Where would you file this?
VCrO4
dinitrogen pentoxide
BaO
platinum (IV) iodate
CBr4
ammonium chlorate
Nb(ClO4)5
potassium iodide
SCl2
nitrogen trichloride
Rb2SO4
manganese (V) sulfide
Write the compound formed by the following ions:
1) Al3+ S22) Mg2+
PO43-
When a formula is given…write the proper name.
When a name is given…write the proper formula.
3) BaO
4) lithium bromide
5) Ni2S3
6) triphosphorus heptoxide
7) N2O5
8) molybdenum (VI) nitride
Write the total number of atoms that make up each compound.
9) trinitrotoluene (TNT)… CH3C6H2(NO2)3
10) phosphoric acid H3PO4
Extra credit: What is the formula for plumbic iodide? (Hint: lead is Pb2+ or Pb4+)
Write the compound formed by the following ions:
1) Al3+ S22) Mg2+
PO43-
When a formula is given…write the proper name.
When a name is given…write the proper formula.
3) BaO
POP
QUIZ
4) lithium bromide
5) Ni2S3
6) triphosphorus heptoxide
7) N2O5
8) molybdenum (VI) nitride
Write the total number of atoms that make up each compound.
9) trinitrotoluene (TNT)… CH3C6H2(NO2)3
10) phosphoric acid H3PO4
Extra credit: What is the formula for plumbic iodide? (Hint: lead is Pb2+ or Pb4+)
Write the compound formed by the following ions:
1) Al3+ S22) Mg2+
PO43-
Answer Key
aluminum sulfide
magnesium phosphate
When a formula is given…write the proper name.
When a name is given…write the proper formula.
3) BaO
Mg3(PO4)2
barium oxide
LiBr
4) lithium bromide
nickel (III) sulfide
5) Ni2S3
P3O7
6) triphosphorus heptoxide
7) N2O5
Al2S3
dinitrogen pentoxide
8) molybdenum (VI) nitride
MoN2
Write the total number of atoms that make up each compound.
9) trinitrotoluene (TNT)… CH3C6H2(NO2)3
10) phosphoric acid H3PO4
21
8
Extra credit: What is the formula for plumbic iodide? (Hint: lead is Pb2+ or Pb4+)
PbI4
Polyatomic Ions - Quiz
C2O42-
……………
oxalate
CrO42-
……………
chromate
Cr2O72-
…………..
dichromate
MnO41-
…………..
permanganate
CH3COO1-
…….
acetate
Exceptions!
Two exceptions to the simple –ide ending are the diatomic oxide ions,
O22- and O21-.
O22- is called peroxide
Note the differences.
O21- is called superoxide.
barium oxide
barium peroxide
BaO
__________
BaO2
__________
sodium oxide
sodium peroxide
Na2O
__________
Na2O2
__________
potassium oxide
potassium superoxide
K2O
__________
KO2
__________
Ba2+
Na1+
Do Not Reduce to lowest terms!
K1+
Naming Chemical Compounds
Binary Compound?
No
Polyatomic ions
present?
No
This is a compound
for which naming
procedures have not yet
been considered.
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 102
Yes
Use the strategy
summarized
earlier
Yes
Name the compound
using procedures similar
to those for naming
binary ionic compounds.
Nomenclature Review Flow Chart
Formula  Name?
Metal + Nonmetal?
(Except: NH4+)
Two Nonmetals?
Ionic
d,f-block
Pb,Sn
Multiple
Columns 1, 2, 13
Ag+, Zn2+
Single
Covalent
Steps 1 & 4 ONLY
1. Write name of cation (metal)
2. Determine the charge on the metal by balancing the
(-) charge from the anion
3. Write the charge of the metal in Roman Numerals
and put in parentheses
4. Write name of anion
(Individual anions need –ide ending!)
Use Prefixes!!!
*Mono*
Di
Tri
Tetra
Penta
Hexa
Hepta
Octa
Nona
Deca
Name  Formula?
No Prefixes?
Ionic
Prefixes?
Covalent
1. Determine the ions present
and the charge on each
(Roman Numeral = cation
charge, otherwise use PT)
1. FORGET CHARGES!!!
2. Balance formula (criss-cross)
3. Do NOT reduce subscripts!
3. Reduce subscripts (if needed)
2. Use prefixes to determine
subscripts
Binary Hydrogen Compounds
of Nonmetals When Dissolved in Water
(These compounds are commonly called acids.)
The prefix hydro- is used to represent hydrogen, followed by the name
of the nonmetal with its ending replaced by the suffix –ic and the word
acid added.
Examples:
*HCl
Hydrochloric acid
HBr
Hydrobromic acid
*The name of this compound would be hydrogen chloride if it was NOT dissolved in water.
Naming Simple Chemical Compounds
Ionic (metal and nonmetal)
Metal
Forms
only one
positive
ion
Use the
name of
element
Forms
more than
one positive
ion
Covalent (2 nonmetals)
Nonmetal
Single
Negative
Ion
Use element
Use the name
name followed
of the
by a Roman
element, but
numeral to
end with ide
show the charge
First
nonmetal
Second
nonmetal
Before
element name
use a prefix
to match
subscript
Use a prefix
before
element name
and end
with ide
Polyatomic
Ion
Use the
name of
polyatomic
ion (ate or
Ite)
Naming Ternary Compounds
from Oxyacids
The following table lists the most common families of oxy acids.
one more
oxygen atom
HClO4
perchloric acid
most
“common”
HClO3
chloric acid
H2SO4
sulfuric acid
H3PO4
phosphoric acid
HNO3
nitric acid
one less
oxygen
HClO2
chlorous acid
H2SO3
sulfurous acid
H3PO3
phosphorous acid
HNO2
nitrous acid
two less
oxygen
HClO
hypochlorous acid
H3PO2
hypophosphorous acid
(HNO)2
hyponitrous acid
An acid with a
name ending in
A salt with a
name ending in
-ous
forms
-ite
-ic
forms
-ate
Hill, Petrucci, General Chemistry An Integrated Approach 1999, page 60
Oxyacids  Oxysalts
If you replace hydrogen with a metal, you have formed an oxysalt.
A salt is a compound consisting of a metal and a non-metal. If the
salt consists of a metal, a nonmetal, and oxygen it is called an
oxysalt. NaClO4, sodium perchlorate, is an oxysalt.
OXYACID
OXYSALT
HClO4
perchloric acid
NaClO4
sodium perchlorate
HClO3
chloric acid
NaClO3
sodium chlorate
HClO2
chlorous acid
NaClO2
sodium chlorite
HClO
hypochlorous acid
NaClO
sodium hypochlorite
ACID
SALT
per stem ic
changes to
per stem ate
stem ic
changes to
stem ate
stem ous
changes to
stem ite
hyper stem ous
changes to
hypo stem ite
HClO3
acid
+
Na1+
cation
NaClO3 + H1+
salt
Suffixes have meaning
“-ide”
binary compound
sodium chloride (NaCl)
“-ite” or “-ate”
sulfite (SO32-)
sulfate (SO42-)
“-ol”
polyatomic compound
“-ate” means one more oxygen
than “-ite”
alcohol
methyl alcohol (methanol)
“-ose”
sugar
sucrose
“-ase”
sucrase
enzyme
Oxidation States in Formulas and Names
Traditional System
Stock System
(Two non-metals)
+1
dinitrogen monoxide
N2O
+3
dinitrogen trioxide
sulfur dioxide
sulfur trioxide
nitrogen (V) oxide
-2
SO2
+6
nitrogen (III) oxide
-2
N2O5
+4
nitrogen (I) oxide
-2
N2O3
+5
dinitrogen pentoxide
-2
sulfur (IV) oxide
-2
SO3
sulfur (VI) oxide
stock system is NOT preferred for two non-metals
Percentage Composition
(by mass...not atoms)
24.305
35.453
Mg
Cl
12
17
magnesium
chlorine
partg
24
% Mg
% == whole
100
95 g xx 100
25.52% Mg
Mg2+
Cl174.48% Cl
MgCl2
It is not 33% Mg and 66% Cl
1 Mg @ 24.305 amu = 24.305 amu
2 Cl @ 35.453 amu = 70.906 amu
95.211 amu
Empirical and Molecular Formulas
A pure compound always consists of the same
elements combined in the same proportions by
weight.
Therefore, we can express molecular
composition as PERCENT BY WEIGHT.
Ethanol, C2H6O
52.13% C
13.15% H
34.72% O
Empirical Formula
Quantitative analysis shows that a compound contains 32.38% sodium,
22.65% sulfur, and 44.99% oxygen.
sodium sulfate
Find the empirical formula of this compound.
 1mol Na 
 =
 23 g Na 
1.408 mol Na / 0.708 mol = 2 Na
32.38% Na
32.38 g Na 
22.65% S
22.65 g S
 1mol S 


32
g
S


= 0.708 mol S / 0.708 mol
=1S
44.99% O
44.99 g O
 1 mol O 


16
g
O


= 2.812 mol O / 0.708 mol
=4O
Step 1) %  g
Step 2) g  mol
Step 3) mol
mol
Na2SO4
Empirical Formula
A sample weighing 250.0 g is analyzed and found to contain the following:
27.38 g
27.38%
1.19%
1.19
g
14.29%
14.29
g
57.14%
57.14
g
Na
sodium
H
hydrogen
C
carbon
O
oxygen
Assume sample is 100 g.
Determine the empirical formula of this compound.
Step 1) convert %  gram
Step 2) gram  moles
  1.1904 mol Na
x mol Na  27.38 g Na1mol Na
/ 1.19 mol = 1 Na
23 g Na 

  1.19 mol H / 1.19 mol = 1 H
x mol H  1.19 g H1mol H

1
g
H


  1.1908 mol C / 1.19 mol = 1 C
x mol C  14.29 g C1mol C

12
g
C



  3.5712 mol O / 1.19 mol = 3 O
x mol O  57.14 g O1mol O

16
g
O


Step 3) mol / mol
NaHCO3
Empirical & Molecular Formula
(contains only hydrogen + carbon)
(~17% hydrogen)
A 175 g hydrocarbon sample is analyzed and found to contain ~83% carbon.
The molar mass of the sample is determined to be 58 g/mol.
Determine the empirical and molecular formula for this sample.
Determine the empirical formula of this compound.
Step 1) convert %  gram
Assume sample is 100 g.
Then, 83 g carbon and 17 g hydrogen.
Step 2) gram  moles
  6.917 mol C
x mol C  83 g C1mol C

/ 6.917 mol = 1 C
12
g
C


  17 mol H / 6.917 mol = 2.5 H
x mol H  17 g H1mol H

1
g
H


(2.4577 H)
2 C @ 12 g = 24 g
5H@ 1g = 5g
29 g
MMempirical = 29 g/mol
CH2.5
C2H5
MMmolecular = 58 g/mol
Step 3) mol / mol
58/29 = 2
Therefore 2(C2H5) = C4H10
butane
Common Mistakes when Calculating Empirical
Formula
Given: Compound consists of 36.3 g Zn and 17.8 g S.
Find: empirical formula
36.3 g Zn
17.8
= 2 Zn
Zn2S
17.8 g S
36.3 g Zn
17.8
= 1S
1 mol Zn
65.4 g Zn
17.8 g S
1 mol S
32.1 g S
1
1
= 0.555 mol Zn
0.555 mol
= 0.555 mol S
0.555 mol
Chemical formula
indicates MOLE ratio,
not GRAM ratio
Zn
ZnS
S
zinc sulfide
Empirical Formula of a Hydrocarbon
burn
in O2
x 1 mol CO2
44.01 g
g CO2
mol CO2
x
2 mol C
1 mol CO2
mol C
mol H
CxHy
g H2O
mol H2O
x 1 mol H2O
18.02 g
Kotz & Treichel, Chemistry & Chemical Reactivity, 3rd Edition , 1996, page 224
x
2 mol H
1 mol H2O
Empirical
formula
Find the molar mass and percentage composition of zinc acetate
Zn2+ CH3COO1acetate = CH3COO1-
Zn(CH3COO)2
1 Zn @ 65.4 g/mol = 65.4 g
/ 183.4 g x 100% = 35.6 % Zn
4 C @ 12 g/mol
= 48 g
/ 183.4 g x 100% = 26.2 % C
6 H @ 1 g/mol
=
/ 183.4 g x 100% = 3.3 % H
4 O @ 16 g/mol
= 64 g
Zn(CH3COO)2
6g
183.4 g
/ 183.4 g x 100% = 34.9 % O
A compound is found to be 45.5% Y and 54.5% Cl.
Its molar mass (molecular mass) is 590 g.
Assume a 100 g sample size
a) Find its empirical formula
45.5 g Y
1 mol Y
= 0.5118 mol Y
/ 0.5118 mol
88.9 g Y
=1Y
YCl3
54.5 g Cl
1 mol Cl
= 1.535 mol Cl
35.5 g Cl
/ 0.5118 mol
= 3 Cl
1 Y @ 88.9 g/mol = 88.9g
b) Find its molecular formula
590 / 195.4
3 Cl @ 35.5 g/mol = 106.5 g
=3
3 (YCl3)
YCl3
Y3Cl9
195.4 g
6.02x1023
Molar Mass
Atomic Mass
vs.
2g
H2 = _____
H2 = _______
2 amu
18 g
H2O = _____
H2O = ________
18 amu
120 g
MgSO4 = _____
MgSO4 = ________
120 amu
g
(NH4)3PO4 = 149
_____
(NH4)3PO4 = ________
149 amu
Percentage Composition (by mass)
% =
part
x 100 %
whole
Empirical vs.
(lowest ratio)
Molecular Formula
Empirical Formula



% g
g  mol
mol
mol
Subscripts, Superscripts and Coefficients
superscripts
Al
2+
3SO4
5 Al3(SO4 )2
coefficient
subscripts
ALUMINUM SULFATE
Subscripts, Superscripts and Coefficients
Mg
2+
2SO4
3 MgSO4
MAGNESIUM SULFATE
Subscripts, Superscripts and Coefficients
Mg
2+
1NO3
4 Mg(NO
MgNO3)22
subscript
MAGNESIUM NITRATE
Interpretation of a Chemical Formula
O
O
O
H
H
S
O
Sulfuric Acid
H2SO4
Two atoms
of hydrogen
One atom
of sulfur
Four atoms
of oxygen
Chemical Formulas
C8H18
Subscript indicates that
there are 8 carbon atoms
in a molecule of octane.
Davis, Metcalfe, Williams, Castka, Modern Chemistry, 1999, page 203
Subscript indicates that
there are 18 hydrogen atoms
in a molecule of octane.
Stock System of Nomenclature
CuCl2
Name of
cation
+
Roman
numeral
indicating
charge
copper (II)
Name of anion
chloride
Chemical Formulas
Al2(SO4)3
Subscript 2
refers to
2 aluminum
atoms.
Davis, Metcalfe, Williams, Castka, Modern Chemistry, 1999, page 204
Subscript 4
refers to
4 oxygen
atoms in
sulfate ion.
Subscript 3 refers to
everything inside parentheses.
Here there are 3 sulfate ions,
with a total of 3 sulfur atoms
and 12 oxygen atoms.
Naming Binary Ionic
Compounds
Al2O3
Name of cation
aluminum
Davis, Metcalfe, Williams, Castka, Modern Chemistry, 1999, page 207
Name of anion
oxide
The OLD System
of Nomenclature
CuCl2
Name of
cation
+
-ic higher
oxidation #
Name of anion
-ous lower
oxidation #
Cupric
Davis, Metcalfe, Williams, Castka, Modern Chemistry, 1999, page 208
chloride
Centrum Multi-Vitamin
Ingredients: ascorbic acid, beta carotene, biotin, calcium pantothenate, calcium
phosphate, carnauba wax, chromium chloride, crospovidone, cupric sulfate,
cyanocobalamin, dl-alpha tocopheryl acetate, FD & C blue no. 2 aluminum lake,
hydroxypropyl cellulose, ferrous fumarate, hydroxypropyl methylcellulose, lactose,
Magnesium oxide, magnesium stearate, manganese sulfate, microcrystalline cellulose,niacinamide, nickel sulfate, phytonandione, polyethylene glycol, potassium
chloride, potassium citrate, potassium iodide, povidone, pyridoxine hydrochloride,
riboflavin, silica gel, sodium borate, sodium metavanadate, sodium molybdate,
sodium selenate, stannous chloride, stearic acid, thiamin mononitrate, titanium
dioxide, triacetin, vitamin A acetate, vitamin D3, zinc oxide.
PC7563-46-00
Warning: Accidental overdose of iron-containing products is a leading cause of
fatal poisoning in children under 6. Keep this product out of reach of children.
In case of accidental overdose, call a doctor or poison control immediately.
Chromium (III) Chloride
RECALL: Chromium forms oxides in which metal exhibits oxidation
states of +3 and +2. STOCK system indicates oxidation
state of compound. Assume Cr3+ (chromium (III) chloride).
Step 1:
Chromium (III)
Step 2:
Cr3+
Cl1-
Step 3:
Cr 1
Cl 3
Step 4:
Chloride
CrCl3
Return to Centrum Bottle
Cupric Sulfate
RECALL: “ic” higher oxidation &
Cu2+ (higher)
“ous” lower oxidation
Cu1+ (lower)
Step 1:
Cupric
Sulfate
Step 2:
Cu2+
SO42-
Step 3:
Cu
Step 4:
Step 5:
2
(SO4) 2
Cu2(SO4)2
CuSO4
Return to Centrum Bottle
Manganese (III) Sulfate
RECALL: Manganese forms oxides in which metal exhibits oxidation
states of +2, +3, +4, and +7. STOCK system indicates oxidation
state of compound. Assume Mn3+ (manganese (III) sulfate).
Step 1:
Manganese (III)
Sulfate
Step 2:
Mn3+
SO42-
Step 3:
Mn 2
(SO4) 3
Step 4:
Mn2(SO4)3
Return to Centrum Bottle
Stannous Chloride
RECALL: “ic” higher oxidation &
Sn4+ (higher)
Step 1:
“ous” lower oxidation
Sn2+ (lower)
Stannous (tin)
Chloride
Step 2:
Sn2+
Cl1-
Step 3:
Sn 1
Cl 2
Step 4:
SnCl2
Return to Centrum Bottle
Stannic Chloride
RECALL: “ic” higher oxidation &
Sn4+ (higher)
“ous” lower oxidation
Sn2+ (lower)
Step 1:
Stannic (tin)
Chloride
Step 2:
Sn4+
Cl1-
Step 3:
Sn 1
Cl 4
Step 4:
SnCl4
Return to Centrum Bottle
Chromium Chloride
RECALL: Chromium has multiple oxidation states.
Name with STOCK system.
Assume Chromiun (II).
Step 1:
Chromium (II)
Step 2:
Cr2+
Cl1-
Step 3:
Cr 1
Cl 2
Step 4:
Cr1Cl2
Step 5:
CrCl2
Chloride
Return to Centrum Bottle
Calcium Phosphate
Step 1:
Calcium
Phosphate
Step 2:
Ca2+
PO43-
Step 3:
Ca
Step 4:
3
(PO4) 2
Ca3(PO4)2
Return to Centrum Bottle
Zinc Oxide
Step 1:
Zinc
Oxide
Step 2:
Zn2+
O2-
Step 3:
Zn
O2
Step 4:
Step 5:
2
Zn2O2
ZnO
Return to Centrum Bottle
Common Polyatomic Ions
Names of Common Polyatomic Ions
Ion
Name
Ion
Name
NH4+
ammonium
CO32-
carbonate
NO2-
nitrite
HCO3-
NO3-
nitrate
SO32-
sulfite
hydrogen carbonate
(bicarbonate is a widely
used common name)
SO42-
sulfate
ClO-
hypochlorite
HSO4-
hydrogen sulfate
(bisulfate is a widely
used common name)
ClO2-
chlorite
ClO3-
chlorate
ClO4-
perchlorate
OH-
hydroxide
C2H3O2-
acetate
CN-
cyanide
MnO4-
permanganate
PO43-
phosphate
Cr2O72-
dichromate
HPO42-
hydrogen phosphate
CrO42-
chromate
H2PO4-
dihydrogen phosphate
O22-
peroxide
Electronegativities
1A
1
Period
2
3
4
5
6
7
8A
H
2.1
2A
3A
4A
5A
6A
7A
Li
Be
B
C
N
O
F
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Al
Si
P
S
Cl
1.5
1.8
2.1
2.5
3.0
Na Mg
1.2
3B
4B
5B
6B
K
Ca Sc
Ti
V
Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br
0.8
1.0
1.3
1.5
1.6
1.6
1.7
1.6
1.8
Rb Sr
Y
Zr Nb Mo Tc Ru Rh Pd Ag Cd
In
Sn Sb Te
0.8
1.2
1.4
1.6
1.8
1.9
2.2
2.2
2.2
1.7
1.7
1.8
Cs Ba
La*
Hf
Ta
W
Re Os
Ir
Pt Au Hg
Tl
Pb Bi
Po At
0.7
1.1
1.3
1.5
1.7
1.9
2.2
2.2
1.8
1.8
2.0
1.0
0.9
y
Fr
Ra Ac
0.7
0.9
1.1
8B
7B
1.5
1.8
2.2
1.8
1B
2B
0.9
1.8
1.9
1.9
2.4
1.9
2.0
1.9
1.9
2.4
2.1
* Lanthanides: 1.1 - 1.3
yActinides:
1.3 - 1.5
Hill, Petrucci, General Chemistry An Integrated Approach 2nd Edition, page 373
Below 1.0
2.0 - 2.4
1.0 - 1.4
2.5 - 2.9
1.5 - 1.9
3.0 - 4.0
2.8
I
2.5
2.2
Review
TWO Elements
Metal (fixed) + Non-metal
binary
NaCl
-ide
Group 1, Group 2, Ag, Zn, Al
sodium chloride
Metal (variable) + Non-metal
Transition Elements
STOCK system (Roman Numeral)
CrCl2
OLD system
chromium (II) chloride
Cr2+
Cl1[-ic (higher) & -ous (lower)]
Cu1+ or Cu2+
CuCl2
Three or more Elements
Polyatomic Ions
Sn
Pb
Cu
Au
Fe
cupric chloride
stannum
plumbum
cuprum
aurum
ferrum
Ternary Compounds
[-ate (one more O) & -ite (one less O)]
LiNO3
lithium nitrate
LiNO2
lithium nitrite
Li3N
lithium nitride
(binary compound)
Polyatomic Ions
1 more oxygen
per____ate
perchlorate
pernitrate
percarbonate
persulfate
perphosphate
ClO41NO41CO42SO52PO53-
[-ate (one more O) & -ite (one less O)]
1 less oxygen
2 less oxygen
_____ite
hypo_____ite
Memorize
NORMAL
_____ate
chlorate
nitrate
carbonate
sulfate
phosphate
ClO31NO31CO32SO42PO43-
chlorite
nitrite
carbonite
sulfite
phosphite
ClO21NO21CO22SO32PO33-
hypochlorite
hyponitrite
hypocarbonite
hyposulfite
hypophosphite
ClO1NO1CO2SO22PO23-
ammonium, cyanide, hydroxide
NH41+
CN1OH1How many atoms are in a formula unit of ammonium hypophosphite?
3 NH41+
PO23-
(NH4)3PO2
Nonmetal & Nonmetal
Mono
Di
Tri
Tetra
1
2
3
4
(Greek prefixes)……DO NOT REDUCE!
Penta
5
Hexa
Hepta
Octa
Nona
Deca
6
7
8
9
10
18
Molecular Models Activity
carbon tetrachloride
ammonia
methane
hydrogen monochloride
water
trichloromethane
ethane
urea
ethyne
propane
dihydrogen monosulfide
butane
carbon dioxide
nitrogen triiodide (video)
supplies
Bonding and Shape of Molecules
Number
of Bonds
Number of
Unshared Pairs
0
3
0
4
0
3
1
2
2
Shape
Examples
-Be-
Linear
BeCl2
Trigonal planar
BF3
Tetrahedral
CH4, SiCl4
Pyramidal
NH3, PCl3
Bent
H2O, H2S, SCl2
B
C
:
2
Covalent
Structure
:
N
O:
Lewis Structures
1) Count up total number of valence electrons
2) Connect all atoms with single bonds
- “multiple” atoms usually on outside
- “single” atoms usually in center;
C always in center,
H always on outside.
Gilbert Lewis
3) Complete octets on exterior atoms (not H, though)
- no unpaired electrons (free radicals)
4) Check
- valence electrons match with Step 1
- all atoms (except H) have an octet; if not, try multiple bonds
- any extra electrons? Put on central atom
Carbon tetrachloride
Cl
Cl C Cl
Cl
CCl4
Cl
C
Cl
109.5o
Cl
Cl
Tetrahedral geometry
Carbon tetrachloride – “carbon tet” had been used as dry cleaning solvent
because of its extreme non-polarity.
Methane
H
HCH
H
H
C
H
109.5o
H
H
Tetrahedral geometry
Methane –The first member of the paraffin (alkane) hydrocarbons series.
a.k.a. (marsh gas, CH4).
Water
d(-)
SO2
Bent
geometry
O
H
H
d(+)
Polar molecule
Ethane
C = 1s22s22p2
H H
HC CH
H H
Lewis dot notation
ball-and-stick
C2H6
molecular formula
space-filling molecule
Ethene
H H
HC CH
H H
Lewis dot notation
ball-and-stick
C2H4
molecular formula
space-filling molecule
Ethyne
No octet
each C “feels” 6 electrons
HC CH
C2H2
HC CH
each C “feels” 7 carbons
Ethyne – a.k.a. “acetylene”
6 electrons = triple bond
HC CH
Stable octet
Dihydrogen monosulfide
SO2
S
H
H
Bent
Carbon dioxide
O C O
CO2
O
C
Linear
geometry
O
O C O
Ammonia
..
..
NH3
N
HH H
N
H
H
H
Trigonal
Pyramidal
geometry
N
H
107o
H
H
Amino Acids – Functional Groups
Amine
Base Pair
Carboxylic Acid
R- COOH
NH21lose H+
NH21-
H+
NH3
NH41+
1+
:
1-
:
:
H
N
N
N
H
H
H
amine
+
H
H
ammonia
H
H
H
ammonium ion
Hydrogen monochloride
H Cl
HCl
d(+)
d(-)
HCl(g) + H2O(l)  HCl(aq)
hydrogen
chloride
Polar molecule
water
hydrochloric
acid
Trichloromethane
d(+)
H
Cl C Cl
Cl
CHCl3
H
C
Cl
109.5o
Cl
Cl
Tetrahedral geometry
H
Cl C Cl
Cl
d(-)
Polar molecule
Urea
NOT “di-urea”
H
H
N
O C
N
H
H
H
H
N
O C
N
H
H
CO(NH2)2
Urea – The first organic compound to be synthesized (Wohler, 1828).
Propane
H H H
HC C CH
H H H
C 3H 8
H
H
C
H
H
C
H
C
H
H
H
Butane
H H H H
HC C C CH
H H H H
H H H
H-C-C-C-C-H
H H H
H
C4H10
H
H
C
H
H
H
C
H
H
C
H
H
C
H
H
Nitrogen triiodide
..
N
I
I
I
NI3
N
I
107o
I
I
Trigonal
Pyramidal
geometry
Video clip:
(slow motion)
detonation of NI3
Supplies







15 black
8 green
1 yellow
4 blue
4 red
42 hydrogen
67 bonds
(carbon)
(chlorine and iodine)
(sulfur)
(oxygen)
(nitrogen)
(hydrogen)
(bonds)
C
Cl
S
I
Cl
Cl C Cl
Cl
H
HCH
H
CCl4
CH4
HCl
CHCl3
H
O C O
H
Cl C Cl
Cl
H Cl
HC CH
C2H2
O N
CO2
S
H H
SH2
H H H H
HC C C CH
H H H H
N
H HH
H H H
HC C CH
H H H
N
I
I
I
Decomposition of Nitrogen Triiodide
Decomposition of Nitrogen Triiodide
N2
NI3
2 NI3(s)
I2
N2(g) + 3 I2(g)
H
H
..
..
C
N
O
109.5o
H
H
H
CH4, methane
lone pair
electrons
107o
H
H
104.5o
H
NH3, ammonia
H2O, water
..
O
O
O
O
O3, ozone
H
O
O
The VSEPR Model
The Shapes of Some Simple ABn Molecules
SO2
..
O
N
S
O
C
O
O
Linear
O
Bent
F
S
O
F
F
O
Trigonal
planar
Trigonal
pyramidal
AB6
F
F
F
Cl
F
F
T-shaped
F
F
F
Square
planar
Brown, LeMay, Bursten, Chemistry The Central Science, 2000, page 305
F
F
P
Xe
F
F
F
S
F
F
F
F
F
Trigonal
bipyramidal
Octahedral
Resources - Nomenclature
Objectives
General Chemistry PP
Worksheet - binary cmpds: single charge cation
Worksheet - binary compounds
Worksheet - ions in chemical formulas
Worksheet - ions in chemical compounds
Worksheet - ionic cmpds: polyatomic ions w multiple-charge cation
Worksheet - ionic formulas (binary, polyatomic, transition)
Worksheet - empirical and molecular
Worksheet - traditional system of nomenclature
Worksheet - covalent binary cmpds: non-metal - non-metal
Worksheet - vocab (bonding)
Worksheet - ionic cmpds: polyatomic ions
Activity - bonding pieces
Worksheet - ionic binary cmpds: multiple charge cation
Activity - molecular models
Worksheet - errors in chemical formulas and nomenclature
Worksheet - oxidation numbers and ionic cmpds
Activity - mole pattern
Textbook - questions
Worksheet - names and formulas of cmpds
Outline (general)