Chapter 3
Chemical Compounds
Compounds
combination of two or more elements
• molecular formulas for • empirical formulas for
ionic compounds
molecular compounds
K2Cr2O7
Naming Binary
Molecular Compounds
Usually more metallic
nonmetal first then
change ending of
second to –ide
Use Greek prefixes for
number, omit mono- for
first nonmetal
1. Mono2. Di-
3. Tri4. Tetra5. Penta6. Hexa7. Hepta-
Binary Molecular Compounds
H2O
NH3
H2S
CO
CS2
N2O4
CCl4
water
ammonia
hydrogen sulfide
carbon monoxide
carbon disulfide
dinitrogen tetroxide
carbon tetrachloride
Which of the following compounds
is NOT named correctly?
nitrogen dioxide
disulfur dichloride
oxygen difluoride
chlorine fluoride
silicon tetrachloride
91%
lic
si
Si
C
l4
tr
a
ch
...
e
te
on
ne
or
i
ch
l
C
lF
0%
f lu
or
id
or
i
flu
n
di
rd
ic
hl
...
de
2% 0%
xy
ge
F2
o
O
S2
C
l2
di
su
lfu
en
di
o
xi
de
7%
2n
it r
og
NO2
S2Cl2
OF2
ClF
SiCl4
N
O
1.
2.
3.
4.
5.
Organic Compounds - Ethanol
Condensed formula
CH3CH2OH
Molecular formula
C2H6O
Hydrocarbons
• alkanes – CnH2n+2
– octane
• alkenes – CnH2n
– Ethylene
H
H
C=C
H
• alkynes – CnH2n-2
– acetylene
H―C≡C―H
H
Alkanes – CnH2n+2
•
•
•
•
•
methane – CH4
ethane – C2H6
propane – C3H8
butanes – C4H10
pentanes – C5H12
•
•
•
•
•
hexanes – C6H14
heptanes – C7H16
octanes – C8H18
nonanes – C9H20
decanes – C10H22
Butane
• Butane molecules are
present in the liquid
and gaseous states in
the lighter
Alcohols
• Replace ―H with ―OH
Alkanes and their Alcohols
Straight & Branch-Chain Alkanes
Some
Common
Alkyl Groups
Alkane Isomers
Naming Branch-Chain Alkanes
• select the longest chain alkane as the base
name
• determine the side chains and give them a
number corresponding to the carbon number
on the base chain
• use Greek prefixes of mono-(1), bi-(2), tri(3),
etc. for multiplicity of same side chain
Naming Branch-Chain Alkanes
CH 3
CH 3
C
CH 3
CH 2
CH
CH 3
2,2,4-trimethylpentane
2,2,4-trimethylpropane
or iso-octane
CH 3
The correct name for
this compound is?
C2H5
3-ethylpropane
3-methylpentane
3-ethylpentane
heptane
2-ethylpentane
43%41%
9%
et
hy
lp
3ro
m
pa
et
ne
hy
lp
en
3ta
et
ne
hy
lp
en
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ne
he
2pt
et
an
hy
e
lp
en
ta
ne
3% 3%
3-
1.
2.
3.
4.
5.
CH3―CH2―CH―CH2―CH3
Cyclic hydrocarbons
IonicCompounds
Characteristics of compounds with ionic
bonding:
• non-volatile, thus high melting points
• solids do not conduct electricity, but melts
(liquid state) do
• many, but not all, are water soluble
Formation of Ionic Compound, NaCl
Valance, Charge on Ions
•
•
•
•
•
compounds have electrical neutrality
metals form positive monatomic ions
non-metals form negative monatomic ions
balance charges
Al3+ O2Al2O3
Valence of Metal Ions
Monatomic Ions
Group IA
 +1
Group IIA
 +2
Maximum positive valence
equals
Group A #
Valence of Non-Metal Ions
Monatomic Ions
Group VIA
Group VIIA
 -2
 -1
Maximum negative valence
equals
(8 – Group A #)
Charges on Some Common
Monatomic Cations and Anions
Common metals with only one ion
• Al3+
• Zn2+
• Ag+
Polyatomic
Ions
Polyatomic Ions
Anions
hydroxide
OH
chromate
CrO 24 
cyanide
CN
dichromate
Cr2O27 
nitrite
NO2
permanganate
MnO 4
nitrate
NO3
hypochlorite
ClO
sulfite
SO23 
chlorite
ClO2
sulfate
SO 24 
chlorate
ClO3
carbonate
CO23 
perchlorate
ClO4
phosphate
PO34
Cation
acetate
C 2H3 O 2
ammonium
HCO3 , HSO3 , HSO4 , HPO24
hydrogen carbonate, ... etc
NH4
-ate and -ite
• NO3nitrate
• NO2nitrite
• -ate is great, -ite is slight
-ate has one more oxygen than –ite
• hypo- under
one less
• percompletely
one more
Name other ions by analogy with
element above
•
•
•
•
SeO42BrO3HSeH2AsO4-
selenate
bromate
hydrogen selenide
dihydrogen arsenate
Permanganate is?
MnO2MgO4MnO42MnO4MnO4-
nO
4-
0%
M
nO
4-
0%
M
nO
42
-
0%
M
gO
4-
0%
M
nO
2-
0%
M
1.
2.
3.
4.
5.
IO
hypoiodite
iodite
iodide
iodate
iodine monoxide
0%
in
e
m
on
o
io
d
xi
de
at
e
0%
io
d
id
e
0%
io
d
ite
0%
io
d
po
i
od
i
te
0%
hy
1.
2.
3.
4.
5.
is?