Chemistry Chapter 7
3-
PO4
phosphate ion
Nomenclature
HC2H3O2
Acetic Acid
C2H3O2acetate ion
There are 3 forms bonding
atoms:
 Ionic—complete transfer of 1 or
more electrons from one atom
to another (one loses, the other
gains)
 Covalent—some valence
electrons shared between
atoms
 Metallic– holds atoms of a metal
together

Most bonds are
somewhere in
between ionic
and covalent.
CATION +
ANION --->
COMPOUND
Na+ + Cl- --> NaCl
A neutral compound
requires
equal number of +
and - charges.
Predicting Charges on Monatomic Ions
OR USE ION CHART
+1 +2
-3 -2 -1
Cd+2
0
A metal atom can
transfer an electron
to a nonmetal.
 The resulting cation
and anion are
attracted to each
other by
electrostatic
forces.

Binary Ionic Compounds:




1. Cation first, then anion
2. Monatomic cation = name of the element
 Ca2+ = calcium ion
3. Monatomic anion = root + -ide
 Cl- = chloride
4. MAKE A NEUTRAL COMPOUND
with subscripts
 CaCl2 = calcium chloride

NaF
-

LiCl
-

MgO
-

NaF
-
sodium fluoride

LiCl
-
lithium chloride

MgO
-
magnesium oxide

Examples:
NaCl
sodium chloride
ZnI2
zinc iodide
Al2O3
aluminum oxide
Complete the names of the following binary
compounds:
Na3P
sodium
________________
KBr
potassium ________________
Al2O3
aluminum ________________
MgS
_________________________
Write the formula for the ionic compound for
barium chloride
It forms between Ba2+ and Cl-.
Write the formula for
Ba2+ and Cl-.
Solution:
1. Balance charge with + and – ions
2. Write the positive ion of metal first, and the
negative ion
Ba2+
ClCl3. Write the number of ions needed as
subscripts
BaCl2
Li+ + N-3 ---->
Li3N
lithium nitride
Ca2+ + I-
----> CaI2
calcium iodide

How do we know how many atoms of each ion we need?

A simple crossing of the charges can answer
that question about 90% of the time.
 Example: Mg2+ and N3-
Mg3N2
Check the charges… 3 x (+2) = +6
2 x (-3) = -6
 When they combined they cancel to yield a
neutral compound.
Write the correct formula for the
compounds containing the following ions:
1.
Na+ , S2a) NaS
b) Na2S
c) NaS2
2.
Al3+, Cla) AlCl3
b) AlCl
c) Al3Cl
3.
Mg2+, N3a) MgN
b) Mg2N3
c) Mg3N2
1. Na+, S2b) Na2S
2. Al3+, Cla) AlCl3
3. Mg2+, N3-
c) Mg3N2
Write the correct formula for the compounds :
1.
calcium oxide
a) CaO
b) Ca2O
c) CaO2
2.
lithium nitride
a) LiN3
b) LiN
c) Li3N
3.
magnesium phosphide
a) MgP
b) Mg2P3
c) Mg3P2
Write the correct formula for the
compounds :
1.
calcium oxide
a) CaO
2.
lithium nitride
c) Li3N
3.
magnesium phosphide
c) Mg3P2
POLYVALENT: Elements that can have
more than one possible charge
MUST have a Roman Numeral
to indicate the charge on the individual ion.
Look at your ion chart…..do you see some?
Elements that can have more than one possible charge
MUST have a Roman Numeral
to indicate the charge on the individual ion.
1+ or 2+
2+ or 3+
Cu+, Cu2+
Fe2+, Fe3+
copper(I) ion
copper (II) ion
iron(II) ion
iron(III) ion
The ROMAN NUMERAL
is the charge on the metal.
If it’s NOT on the ion chart,
you can still do the work!
tin (IV) = Sn4+
chromium (VI) = Cr6+
These compounds
REQUIRE Roman Numerals
because they have metals that can have
more than one possible charge:
FeCl3
CuCl
SnF4
PbCl2
Fe2S3
(Fe3+)
(Cu+ )
(Sn4+)
(Pb2+)
(Fe3+)
iron (III) chloride
copper (I) chloride
tin (IV) fluoride
lead (II) chloride
iron (III) sulfide
How can you tell which one it is?
FeCl3
(Fe2+)
(Fe3+)
Is it iron (II) or iron(III)
iron (II) chloride
iron (III) chloride
Work backwards from anion.
Figure out both choices and match OR
Inverse criss-cross (only works sometimes)
Complete the names of the following binary
compounds with variable metal ions:
FeBr2
iron (_____) bromide
CuCl
copper (_____) chloride
SnO2
___(_____ ) ______________
Fe2O3
________________________
Hg2S
________________________
Complete the names of the following binary
compounds with variable metal ions:
FeBr2
iron ( II ) bromide
CuCl
copper (_____) chloride
SnO2
___(_____ ) ______________
Fe2O3
________________________
Hg2S
________________________
Complete the names of the following binary
compounds with variable metal ions:
FeBr2
iron ( II ) bromide
CuCl
copper ( I ) chloride
SnO2
___(_____ ) ______________
Fe2O3
________________________
Hg2S
________________________
Complete the names of the following binary
compounds with variable metal ions:
FeBr2
iron ( II ) bromide
CuCl
copper ( I ) chloride
SnO2
tin (IV) oxide
exception to inverse criss-cross
Fe2O3
________________________
Hg2S
________________________
-
NO3
nitrate ion
NO2nitrite ion
NH4
+
More than one
element in the ion!
Cl
Only one element.
ammonium chloride, NH4Cl
NH4
+
More than one
element in the ion!
ammonium chloride, NH4Cl
Cl
Only one element.
SPECIAL NAME for POLYATOMIC IONS:
Can you see them on your ion chart?
Writing Formulas
SAME:
 Write

each ion, cation first.
Don’t show charges in the final formula.
 Overall


charge must equal zero.
If charges cancel, just write symbols.
If not equal to zero, use subscripts to balance charges.
Writing Formulas
 Write

each ion, cation first.
Don’t show charges in the final formula.
 Overall



charge must equal zero.
If charges cancel, just write symbols.
 EXACTLY as appear on ion chart.
 POLYATOMIC may have subscripts.
If not equal to zero, use subscripts to balance charges.
Use parentheses to show more than one of a particular
polyatomic ion.
Writing Formulas
magnesium phosphate
 Write
each ion, cation first.
 Overall


charge must equal zero.
If charges cancel, just write symbols.
 EXACTLY as appear on ion chart for polyatomic.
 POLYATOMIC may have subscripts.
If not equal to zero: Use parentheses to show more
than one of a particular polyatomic ion and use
subscripts to balance charges.

How do we know how many atoms of each ion we need?

A simple crossing of the charges can answer
that question about 90% of the time.
 Example: Mg2+ and PO43-
Mg3(PO4)2
Check the charges… 3 x (+2) = +6
2 x (-3) = -6
 When they combined they cancel to yield a
neutral compound.


The crossing technique does not work if the
magnitude of the charges is the same
Example: Mg2+ and CO32-
Mg2(CO3)2
This is incorrect since we want the lowest
ratio possible which is 1:1 to yield
MgCO3
Sodium Sulfate
Na+ and SO4 -2
Na2SO4
Iron (III) hydroxide
Fe+3 and OHFe(OH)3
Ammonium carbonate
NH4+ and CO3 –2
(NH4)2CO3
Cd(OH)2
cadmium hydroxide
Na2SO4
sodium sulfate
Ca(ClO2)2
calcium chlorite
Na2SO3
sodium sulfite
AgCN
silver cyanide
KClO3
potassium chlorate
1. aluminum nitrate
a) AlNO3
b) Al(NO)3
c) Al(NO3)3
2. copper(II) nitrate
a) CuNO3
b) Cu(NO3)2
c) Cu2(NO3)
3. Iron (III) hydroxide
a) FeOH
b) Fe3OH
c) Fe(OH)3
4. Tin(IV) hydroxide
a) Sn(OH)4 b) Sn(OH)2
c) Sn4(OH)



Contains at least 3 elements
There MUST be at least one polyatomic ion
(it helps to circle the ions)
Examples:
NaNO3
sodium nitrate
K2SO4
potassium sulfate
Al(HCO3)3
aluminum bicarbonate
or
aluminum hydrogen carbonate
Match each set with the correct name:
1. Na2CO3
a) magnesium sulfite
MgSO3
b) magnesium sulfate
MgSO4
c) sodium carbonate
2.
Ca(HCO3)2
CaCO3
a) calcium carbonate
b) calcium phosphate
Ca3(PO4)2
c) calcium bicarbonate
Name the following:
1.
Na2O
2.
CaCO3
3.
PbS2
4.
Sn3N2
5.
Cu3PO4
6.
HgF2
Write the formula:
1.
copper (II) chlorate
2.
calcium nitride
3.
aluminum carbonate
4.
potassium bromide
5.
barium fluoride
6.
cesium hydroxide
CO2 Carbon dioxide
CH4 methane
BCl3
boron trichloride
All are
formed from
two or more
nonmetals.
Ionic
compounds
generally
involve a metal
and nonmetal
(NaCl)
A covalent compound is formed by sharing electrons
between 2 nonmetals or metalloids.
These compounds are usually molecular and are
named using a prefix system.
When naming these compounds name the element
further to the left (in the periodic table) first, then
the one on the right.
You name the first element using the exact element name.
Name the second element by writing the root of the
element’s name and add the suffix “–ide.”
If there is more than one atom of any given element, you
add the Greek prefix denoting how many atoms of that
element are present. Use list of Greek prefixes.
If only one atom of the second element is
present it gets the prefix “mono”, but not for
the first element.
PREFIX
monoditritetrapentahexaheptaoctanonadeca-
NUMBER
1
2
3
4
5
6
7
8
9
10
Here are some examples of prefix names
for binary molecular compounds.
PF5 phosphorus pentafluoride
SO2 sulfur dioxide
SF6 sulfur hexafluoride
N2O4 dinitrogen tetroxide
CO carbon monoxide

Prefix System (binary molecular compounds)
1.
Add prefixes to indicate # of atoms.
2.
Omit mono- prefix on the FIRST element.
Mono- must be used on the SECOND element .
3.
Change the ending of the second element to -ide.
Do the reverse for
writing formulas!
• CCl4
• carbon tetrachloride
• N 2O
• dinitrogen monoxide
• SF6
• sulfur hexafluoride
• arsenic trichloride
• AsCl3
• dinitrogen pentoxide
• N2O5
• tetraphosphorus decoxide
• P4O10
Fill in the blanks to complete the following
names of covalent compounds.
CO
carbon ______oxide
CO2
carbon _______________
PCl3
phosphorus _______chloride
CCl4
carbon ________chloride
N2O
_____nitrogen _____oxide
1.
P2O5
a) phosphorus oxide
b) phosphorus pentoxide
c) diphosphorus pentoxide
2.
Cl2O7
a) dichlorine heptoxide
b) dichlorine oxide
c) chlorine heptoxide
3.
Cl2
a) chlorine
b) dichlorine
c) dichloride
Name the following compounds:
1. CaO
a) calcium oxide
b) calcium(I) oxide
c) calcium (II) oxide
2.
3.
SnCl4
a) tin tetrachloride
c) tin(IV) chloride
b) tin(II) chloride
N2O3
a) nitrogen oxide
c) nitrogen trioxide
b) dinitrogen trioxide
Name the following compounds:
1.
CaO
a) calcium oxide
2.
SnCl4
c) tin(IV) chloride
3.
N2O3
b) dinitrogen trioxide
1.
2.
3.
4.
5.
6.
7.
8.
9.
dinitrogen monoxide
potassium sulfide
copper (II) nitrate
dichlorine heptoxide
chromium (III) sulfate
iron (III) sulfite
calcium oxide
barium carbonate
iodine monochloride
1.
2.
3.
4.
5.
6.
7.
8.
9.
BaI2
P4S3
Ca(OH)2
FeCO3
Na2Cr2O7
I2O5
Cu(ClO4)2
CS2
B2Cl4


Acids

Compounds that form H+ in water.

Formulas usually begin with ‘H’.

In order to be an acid instead of a gas, binary acids
must be aqueous (dissolved in water)

Ternary acids are ALL aqueous
Examples:

HCl (aq) – hydrochloric acid

HNO3 – nitric acid

H2SO4 – sulfuric acid
Anion
Ending
Acid Name
No Oxygen
-ide
hydro-(stem)-ic acid
w/Oxygen
-ate
(stem)-ic acid
-ite
(stem)-ous acid
An easy way to remember which goes with which…
“In the cafeteria, you ATE something ICky”
ACIDS
start with 'H'
2 elements
3 elements
hydro- prefix
-ic ending
no hydro- prefix
-ate ending
becomes
-ic ending
-ite ending
becomes
-ous ending
• HBr (aq)
• 2 elements, -ide

hydrobromic acid

carbonic acid

sulfurous acid
• H2CO3
• 3 elements, -ate
• H2SO3
• 3 elements, -ite
• hydrofluoric acid
• 2 elements
 H+ F-
 HF (aq)
• sulfuric acid
• 3 elements, -ic
 H+ SO42-  H2SO4
• nitrous acid
• 3 elements, -ous
 H+ NO2-
 HNO2

HI (aq)

HCl

H2SO3

HNO3

HIO4

Hydrobromic acid

Nitrous acid

Carbonic acid

Phosphoric acid

Hydrotelluric acid
Nomenclature Summary Flowchart