NOMENCLATURE

1
NOMENCLATURE
OF IONIC
COMPOUNDS
2
IONIC COMPOUNDS
Compounds are two or more elements that are held
together by opposite charge attraction.
8 ()10 (-)-2 Charge
Oxygen-8
Magnesium-12
12 ()10 (-)2 Charge
Metal
Non-metal
3
Metals combine with non-metals Metals loose
electrons to non-metals They then attract because
their charges will be opposite.
Metals
4
Negative Ions (single atoms)
-3
-2
-1

• Most of the negative ions have a set negative
  charge

5
Metals in groups 1A, 2A, and 3A have set positive
charges when they lose electrons. So does Zn,
Cd, Ag. They are attracted to either a single
non-metal ion or a polyatomic ion
1
3
2
1
2
6
POLYATOMIC IONS (charged building
blocks)Polyatomic ions are mostly made of two
non-metals.
Ions with -1 charge perbromate BrO4-1 bromate
BrO3-1 bromite BrO2-1 hypobromite
BrO-1 perchlorate ClO4-1 chlorate
ClO3-1 chlorite ClO2-1 hypochlorite
ClO-1 periodate IO4-1 iodate
IO3-1 iodite IO2-1 hypoiodite
IO-1
nitrate NO3-1 nitrite NO2-1 hydroxide OH-1 cyanid
e CN-1 acetate C2H3O2-1 Permanganate MnO4-1 bicar
bonate HCO3-1 Ions with a -2 Charge carbonate CO3
-2 sulfate SO4-2
sulfite SO3-2 chromate
CrO4-2 dichromate Cr2O7-2 oxalate
C2O4-2 Ions with a -3 Charge phosphate
PO4-3 phosphite PO3-3 arsenate
AsO4-3 Ions with 1 charge ammonium ion NH41
7
These polyatomic ions match the charge of their
group
-1
Ions with -1 charge perbromate BrO4-1 bromate
BrO3-1 bromite BrO2-1 hypobromite
BrO-1 perchlorate ClO4-1 chlorate
ClO3-1 chlorite ClO2-1 hypochlorite
ClO-1 periodate IO4-1 iodate
IO3-1 iodite IO2-1 hypoiodite
IO-1
8
These polyatomic ions match the charge of their
group
Ions with a -2 Charge sulfate SO4-2 sulfite
SO3-2 Ions with a -3 Charge phosphate
PO4-3 phosphite PO3-3
-3
-2
9

• It is also important to memorize the oxidation
  of the ions that have fixed oxidation numbers
  (positive or negative). In particular, those
  from groups 1A, 2A, 3A, 4A, 5A, 6A, 7A, 8A and
  the elements Zn, Cd and Ag. Use the following
  periodic chart to determine their oxidation
  numbers. Just click on the element symbol

10
Elements with Fixed Oxidation Numbers
1
2
3
0
-4
-3
-2
-1
8A
7A
1A
H
H
He
6A
5A
4A
3A
2A
N
B
C
O
F
Ne
Li
Be
Click on element to see its oxidation number(s)
Al
Si
P
S
Cl
Ar
Na
Mg
Sc
Ti
V
Cr
Mn
Fe
K
Ca
Ga
Ge
As
Se
Br
Kr
Co
Ni
Cu
Zn
Y
Zr
Nb
Mo
Tc
Ru
Rb
Sr
In
Sn
Sb
Te
I
Xe
Rh
Pd
Ag
Cd
La
Hf
Ta
Re
Os
Ce
Ba
Tl
Pb
Bi
Po
At
Rn
Ir
Pt
Au
Hg
W
Ac
Rf
Db
Sg
Rh
Hs
Fr
Ra
Mt
Next Slide
11
Naming Ionic Compounds

• The positive ion (usually a metal) is named first
  while the negative ion (a non-metal or a
  polyatomic ion) is named last.
• The charge on the negative ion is used to
  determine the charge on the positive ion.
• In-order for the total oxidation state to be
  zero, the total positive charge must equal the
  total negative charge. A simple algebraic
  equation can be used to determine the charge on a
  single metal ion.
• This charge is expressed as a Roman Numeral in
  parenthesis that immediately follows the name of
  the metal.

CuSO4 Cu?SO4-2 x (-2)0 X 2
Copper (II) Sulfate
12
Naming Ionic Compounds

• The positive ion (usually a metal) is named first
  while the negative ion (a non-metal or a
  polyatomic ion) is named last.
• The charge on the negative ion is used to
  determine the charge on the positive ion.
• In-order for the total oxidation state to be
  zero, the total positive charge must equal the
  total negative charge. A simple algebraic
  equation can be used to determine the charge on a
  single metal ion.
• This charge is expressed as a Roman Numeral in
  parenthesis that immediately follows the name of
  the metal.

Cu2SO4 Cu2xSO4-2 2x (-2)0 x 1
Copper (I) Sulfate
13
Naming Ionic Compounds

• If the positive ion is one that has a fixed
  oxidation number then no Roman Numeral is used.
• Everyone should know the charge of fixed ions.
  These include metals in group 1A, 2A and the
  specific metals Al, Zn, Cd Ag (zinc, cadmium
  and silver).

CaSO4
Calcium Sulfate
No Roman Numeral
14
Examples 1- Formulas to Names

• CuSO3

1. Write the names of the ions
0
-2
2. Determine the charge of the positive ion
Cu
SO3
2
x
X (- 2) 0
Im a polyatomic ion
You must know the charge on the sulfite ion is -2
The sum of the positive and negative charges must
equal zero
2 2
X 2
copper
sulfite
(II)
Final Name
Next
15
Examples 2- Formulas to Names
1. Write the names of the ions
Im a polyatomic ion

• KMnO4

potassium
permanganate
Final Name
If the positive ion has a fixed charge, you are
finished.
16
Examples 3- Formulas to Names
1. Write the names of the ions
2. Determine the charge of the positive ion
Im a polyatomic ion

• NH4NO3

ammonium
nitrate
Final Name
If the positive ion has a fixed charge, you are
finished.
17
Examples 4- Formulas to Names
1. Write the names of the ions
2. Determine the charge of the positive ion
X 2
X 2(-1) 0
Snx (F-1)2 0
Im not a polyatomic ion

• SnF2

tin
fluoride
(II)
Final Name
18
Examples 5- Formulas to Names
1. Write the names of the ions
2. Determine the charge of the positive ion
Im a polyatomic ion

• Ba(ClO4)2

barium
perchlorate
Final Name
If the positive ion has a fixed charge, you are
finished.
19
Examples 6- Formulas to Names
1. Write the names of the ions
2. Determine the charge of the positive ion
X 1
2X (-2) 0
2Cux (S)-2 0
Im not a polyatomic ion

• Cu2S

copper
sulfide
(I)
Final Name
20
Examples 6- Formulas to Names

• Cu2S

1. Write the names of the ions
-2
2. Determine the charge of the positive ion
(Cu )2
S
1
x
2X (- 2) 0
The sum of the positive and negative charges must
equal zero
You must know the charge on the sulfide ion is -2
2 2
2X 2
X 1
copper
sulfide
(I)
Final Name
Next
21
Examples 7- Formulas to Names
1. Write the names of the ions
2. Determine the charge of the positive ion
X 1
2X (-2) 0
2(Nax)(Cr2O7)-2 0
Im a polyatomic ion

• Na2Cr2O7

sodium
dichromate
(I)
If the positive ion has a fixed charge, it is not
shown
Final Name
22
Examples 9- Formulas to Names
1. Write the names of the ions
Im a hydrated compound, this part will be named
last
2. Determine the charge of the positive ion
X 3
X (-3) 0
Fex (PO3 -3) 0
Im a polyatomic ion

• FePO3 .3H2O

.3H2O
3
iron
phosphite
tri
hydrate
(III)
Final Name
23
Examples 10- Formulas to Names
1. Write the names of the ions
2. Determine the charge of the positive ion
Im a polyatomic ion

• LiCN

lithium
cyanide
If the positive ion has a fixed charge, you are
finished.
Final Name
24
Writing Ionic Formulas

• It is easier to write the formula of an ionic
  compound from its name than the reverse.
• The oxidation number of the negative ion must be
  memorized in all cases. Refer to the table of
  polyatomic ions.

25
Example 1-Names to Formulas
1. Write symbols of elements
2. Determine number of ions
Al Cl-1
3

• aluminum chloride

If there is no Roman Numeral, you need to know
the fixed oxidation number of the positive ion.

Cl
Al
3
1
Final Formula
If there is only one atom the 1 is not shown
Next
26
Example 2-Names to Formulas
1. Write symbols of elements
2. Determine number of ions
(Co2)(BrO3-1) 0

• cobalt(II) bromate

BrO3
(BrO3)2
Co
Final Formula
Next
27
Example 3-Names to Formulas
1. Write symbols of elements
2. Determine number of ions
(Ni3)x(C2H3O2-1)y 0

• nickel(III) acetate

(C2H3O2)3
C2H3O2
Ni
Final Formula
Next
28
Example 4-Names to Formulas
1. Write symbols of elements
2. Determine number of ions
(Li )x(PO4-3)y 0
1

• lithium phosphate

If there is no Roman Numeral, you need to know
the fixed oxidation number of the positive ion.

PO4
(PO4)
Li
3
Final Formula
Next
29
Practice Problems

• By now you should have an idea of what is
  expected when naming covalent binary compounds
  using prefixes.
• In order to master this naming system you need
  to practice until you feel proficient in naming
  compounds using prefixes.

30
Practice Problem 1

• Fe(NO3)3

Choose the correct name for the compound
1. Iron trinitrate
No, you do not use prefixes
2. iron(I) nitrate
No, you have the wrong oxidation number
3. iron(III) nitrite
No, you need to review polyatomic ions
4. iron(III) nitrate
Very good, click arrow to continue
5. none of the above
No, there is a correct answer
next problem
Polyatomic Ions
Periodic Chart
31
Practice Problem 2

• sodium chlorite

Choose the correct formula for the compound
1. NaCl
No
2. NaClO
No
3. NaClO2
Very good, click arrow to continue
No
4. Na(ClO)2
No, there is a correct answer
5. none of the above
End
Periodic Chart
32
POLYATOMIC IONS
Ions with -1 charge perbromate BrO4-1 bromate
BrO3-1 bromite BrO2-1 hypobromite
BrO-1 perchlorate ClO4-1 chlorate
ClO3-1 chlorite ClO2-1 hypochlorite
ClO-1 periodate IO4-1 iodate
IO3-1 iodite IO2-1 hypoiodite
IO-1
nitrate NO3-1 nitrite
NO2-1 hydroxide OH-1 cyanide
CN-1 thiocyanate SCN-1 acetate
C2H3O2-1 Permanganate MnO4-1 bicarbonate
HCO3-1 Ions with a -2 Charge carbonate
CO3-2 phthalate C8H4O4-2 sulfate
SO4-2
sulfite SO3-2 chromate
CrO4-2 dichromate Cr2O7-2 oxalate
C2O4-2 peroxide O2-2 Ions with a -3
Charge phosphate PO4-3 phosphite
PO3-3 arsenate AsO4-3 Ions with 1
charge ammonium ion NH41
return
33
Oxidation Numbers (most common)
1
2
3
0
-4
-3
-2
-1
1A
8A
7A
H
H
He
6A
5A
4A
3A
2A
N
B
C
O
F
Ne
Li
Be
Click on element to see its oxidation number(s)
Al
Si
P
S
Cl
Ar
Na
Mg
Sc
Ti
V
Cr
Mn
Fe
K
Ca
Ga
Ge
As
Se
Br
Kr
Co
Ni
Cu
Zn
Y
Zr
Nb
Mo
Tc
Ru
Rb
Sr
In
Sn
Sb
Te
I
Xe
Rh
Pd
Ag
Cd
La
Hf
Ta
Re
Os
Ce
Ba
Tl
Pb
Bi
Po
At
Rn
Ir
Pt
Au
Hg
W
Ac
Rf
Db
Sg
Rh
Hs
Fr
Ra
Mt
Nd
Pm
Sm
Eu
Gd
Tb
Ce
Pr
Yb
Lu
Dy
Ho
Er
Tm
return
Np
Am
Cm
Bk
Th
Pa
No
Lr
Cf
Es
Fm
Md
U
Pu