Chemical Names &
Formulas
Chapter 9
Warm Up

Take 7 min to finish Homework
Go Over

ChemQuest 21

Skill Practice 19-21

More Ionic Bonding Practice
Time to Review Ionic Bonding

IB QUIZ NEXT CLASS

This should go quick. All of this has
been taught. Some of these slides you
have already seen
Ionic Bonding: Between Metals and Nonmetals
Monatomic Ions
 Ions
consisting of one atom
 Determined by using the periodic table

Transition Metals - the charge must be
provided
Ex.)
Fe(III) has a +3 charge
Fe(II) has a +2 charge

Reference Table 9.2, p.255 for trans. metal
names and charges
 Stock Name vs. Classical Name
 Ex)
Copper(I) ion (stock name) and Cuprous ion
(classical name)
Polyatomic Ions
 Tightly
bound group of atoms that
behave as a unit and carry a charge
 Treated the same as monatomic ions
when writing chemical formulas and
naming (also called tertiary compounds)
Ex.)
(PO4)3- Phosphate
(CO3)2-
Carbonate
Polyatomic Ions
Types of Compounds

Ionic
– Metal & Non-Metal

Molecular
– 2 Non-Metals
Ionic Compounds

Ionic bond forms between ions (atoms w/ a
charge b/c they have extra or missing e-)
– Represented by chemical formulas (or formula
units)
• Ex) NaCl
– Typically solids at room temperature

Occurs between oppositely charged ions
(“opposites attract”)
 Include a cation & an anion
Cation = + charges
Anion = - charges
 In
an ionic compound, the atoms
combine in ratios to balance the
charges (neutral compound)
Ex.) How many Mg will react w/ S?
2+
Mg
+
2S
 MgS
Criss-Cross Method

An easier way to determine the
subscripts

Use it if it makes sense to you.
Otherwise, continue balancing the
charges
Criss-Cross Method:

How many B will react w/ S?
B3+ & S2-
B
3+
2
+
S
23
B2S3
Notice: when you write the formula the cation
(metal) goes 1st
Examples:
What is the formula when Al and F
combine?
Al3+ & F1-
Al
1
3+
+
F
13
AlF3
Examples:
Lithium and Bromine
Calcium and Sulfur
LiBr
CaS
Zn (II) and Phosphorus
Sodium and Phosphate
Zn3P2
Na3PO4
Naming Ionic Compounds
 Binary
compounds - composed of 2
elements
1st write the name of the cation
2nd write the name of the anion
Replace the ending with “-ide”
Examples:
Al2O3
CaO
Aluminum Oxide
Sodium Chloride
Calcium Oxide
FeS
Iron(II) Sulfide
CuBr2
Copper(II) Bromide
NaCl
Naming Ionic Compounds with
Polyatomic Ions
 composed
of 3 or more different
elements
1st write the name of the cation
2nd write the name of the
polyatomic ion
Examples:
Al(NO3)3
Aluminum Nitrate
Na(OH)
Sodium Hydroxide
Ca(SO4)
Calcium Sulfate
Fe(CrO4)
Iron(II) Chromate
Cu3(PO4)
Copper(I) Phosphate
Naming Race Worksheet
Second Page (Front/Back) of packet
 Work with ONE partner OR by yourself
 Do all 45
 Get answers checked by me
 First group done:

Naming Acids

Use the template below to name acids:
Anion Example
ending
- ide
HCl
Chloride
- ite
H2SO3
Sulfite
- ate
HNO3
Nitrate
Acid name
Hydro(
(
(
)-ic acid
Example
Hydrochloric
acid
) – ous
acid
Sulfurous
acid
) – ic acid
Nitric acid
Properties of IB
Properties
- Electrically neutral compounds
- High boiling/melting point (BP/MP)
- Form crystal solids which are brittle
- Dissolve in Water
- Conduct electricity in molten or
dissolved state
Ionic Compounds
Dissociate into ions when they dissolve
 So,

– NaCl
– AlCl3

Na+ + ClAl+3 + 3Cl-
Note: The number of each ion becomes a
coefficient (3Cl-)
 Ions have a charge, so the charge MUST be
written
Write the equation when the
following ionic compounds
dissolve in water
MgO
 Na3P
 Fe2O3
 Mg(NO3)2
 FeSO4

Work on Ionic Bonding Practice

First Page (Front/Back) of Packet
STOP

Complete any unfinished worksheets
Molecular Compounds
 Compounds
composed of molecules
(usually 2 or more non-metals)
– Represented by molecular formulas
• Ex) H2O
– Typically exist as gasses or liquids at
room temperature
 Diatomic
molecules
– H2, N2, O2 , F2 , Cl2 , Br2 , I2
Naming Molecular Compounds
 Binary
molecular compounds composed of 2 non-metals
– Use prefixes to distinguish
between different compounds
(Table 6.5, p.159)
– Atom which is furthest to the
left is written first
Prefix
MonoDiTriTetraPentaHexaHeptaOctaNonaDeca-
Number
1
2
3
4
5
6
7
8
9
10
Examples:
SO3
Sulfur trioxide
CO
Carbon Monoxide
OF6
Oxygen Hexafluoride
P2Br4
Diphosphorus
tetrabromide
Trisulfur Octiodide
S3I8
Examples

Name the following acids
– HBr
– HNO2
– H2SO4

Write the formula for the following acids
– Hydrofluoric acid
– Phosphorous acid
The Law of Definite Proportions

the masses of the elements are always
in the same proportions in any sample
of a chemical compound
8:1
16:1
The Law of Multiple Proportions

Comparison of the ratios of one element
in 2 different compounds containing that
particular element
Example:

A sample of water contains 16 g of
oxygen, whereas a sample of hydrogen
peroxide contains 32 g of oxygen. What
is the ratio of oxygen in the two
compounds?