1. Chapter 7: Chemical Nomenclature
OBJECTIVES
Name compounds given a formula
Write formulas given a name
Calculate moles, mass, and particles (CH 3)
Find oxidation states of atoms
Calculate molecular and empirical formulas
Determine percent composition of a substance
Calculate solution concentration (molarity)

2. A. The Formula What’s in a name? Well, way more than you think IUPAC
_________
Systematic rules for naming Ionic and Covalent molecules governed by this organization. International Union of Pure and Applied Chemists.
C8H18
Al2(SO4)3

3. A. The Formula C H
C8H18
SO4 S O
SO4
Al2(SO4)3 Al Al
SO4

4. B. Naming – Ionic Compounds
cation followed by anion
Formulas have a system:___________________
What are cations?
What are anions?
+ charged; usually metals
- charged; usually nonmetals
How do you name cations?
Easy: name of the metal (or other element)
Al+3 =
C+4 =
Aluminum cation
Carbon cation

5. B. Naming - Ionic Compounds
How do you name anions?
Drop last syllable (or 2) and add ‘-ide’ suffix
Anion
Name F-
Cl-
O-2
S-2
N-3
P-3
Fluoride
Chloride
Oxide
Sulfide
Nitride
Phosphide

6. B. Naming - Ionic Compounds
NaCl
SrF2
Al2O3
Li3N
sodium chloride Na Cl
strontium fluoride F Sr Al O
aluminum oxide Li N
lithium nitride

7. B. Naming - Ionic Compounds
Formula Writing – Rubidium sulfide
1. Write symbols
Rb S
Rb S +1 -2
2. Write valence above
3. Ignore signs, criss-cross 1 2
Rb S
4. Ignore 1’s and reduce
charge should = 0
Rb2S Rb S
2Rb = +2; S = -2

8. B. Naming - Ionic Compounds
FORMULAS
rubidium selenide
cesium sulfide
radium silicide

9. C. Naming – Polyatomic Ions
Some groups of atoms occur so often, they are named. -1 +1
NH4
C2H3O2 orCH3COO CN
HCO3 OH
NO3
NO2
PO4
Ammonium
Acetate
Cyanide
Bicarbonate
Hydroxide
Nitrate
Nitrite
Phosphate
ClO3
ClO2
ClO
ClO4
MnO4
CrO4
CO3
SO4
SO3
Chlorate
Chlorite
Hypochlorite
Perchlorate
Permanganate
Chromate
Carbonate
Sulfate
Sulfite -1 -1 -1 -1 -1 -1 -1 -1 -1 -2 -1 -2 -1 -2 -2 -3

10. C. Naming – Polyatomic Ions
Rb2SO4
Rubidium Sulfate
H2CO3
Hydrogen Carbonate (AKA carbonic acid)
Calcium Cyanide
Ammonium Hydroxide

11. D. Naming – Transition metals, tin and lead
These elements have more than 1 valence. We name them using the STOCK SYSTEM. Use roman numerals to give the charge of the metal. +2 -2 Cu
SO4
Copper (II) sulfate Cu
SO4 +1 -2
Cu2
SO4
Copper (I) sulfate Cu
SO4
Tells you the charge
Two Exceptions:
Zn = +2
Ag =+1

12. D. Naming – Transition metals, tin and lead
Pb(NO3)2
Sn(SO3)2
lead (III) nitrate

13. E. Naming covalent compounds
What is a covalent compound?
Ionic
Covalent
Covalent compounds are made of non metals with no polyatomic ions!
(NH4)2S
H2O
TiCl4 NO
PtSi
P4O10
MgBr2
Cl2F2
Na2SO3
N2O6
What’s the diff?

14. D. Naming covalent compounds
Covalent compounds use a prefix system:
Mono Di
Tri
Tetra
Penta
Hexa
Hepta
Octa
Nona
Deca
1 – used only for Oxygen when it’s last 2 3 4 5 6 7 8 9 10

15. E. Naming covalent Compounds
dinitrogen monoxide
N2O
oxygen trifluoride
OF3
N2O4
dinitrogen tetroxide
NOT TETRAOXIDE

16. F. Common Names HCl HNO3 H2SO4 HCH3COO NH3 NaHCO3 CaCO3 NaClO NaOH
Formula
Common Name
IUPAC Name
HCl
HNO3
H2SO4
HCH3COO
NH3
NaHCO3
CaCO3
NaClO
NaOH
SiO2
Hydrochloric acid
Nitric Acid
Battery Acid
Sulfuric Acid
Vinegar
Acetic Acid
Ammonia
Azane
Sodium bicarbonate
Baking soda
Chalk
Calcium carbonate
Bleach
Sodium hypochlorite
Lye/Caustic Soda
Sodium hydroxide
Sand/Quartz
Silicon dioxide

17. G. Percent Composition
the percentage by mass of each element in a compound

18. 28 g 36 g %Fe =  100 = 78% Fe 8.0 g 36 g %O =  100 = 22% O
G. Percent Composition
Find the percentage composition of a sample that is 28 g Fe and 8.0 g O.
28 g
36 g
%Fe =
 100 =
78% Fe
8.0 g
36 g
%O =
 100 =
22% O

19. G. Percent Composition
Find the % composition of Cu2S.
g Cu
g Cu2S
%Cu =
 100 =
79.852% Cu
32.07 g S
g Cu2S
%S =
 100 =
20.15% S

20. C2H6 CH3 H. Empirical Formula
Smallest whole number ratio of atoms in a compound
C2H6
reduce subscripts
CH3

21. 1. If % given, assume you have 100g and the percents become masses.
H. Empirical Formula
1. If % given, assume you have 100g and the percents become masses.
2. Find moles of each element.
3. Divide moles by the smallest # to find subscripts.
4. When necessary, multiply subscripts by 2, 3, or 4 to get whole #’s.

22. Find the empirical formula for a sample of 25.9% N and 74.1% O.
H. Empirical Formula
Find the empirical formula for a sample of 25.9% N and 74.1% O.
Assume 100g; therefore:
25.9 g N and 74.1 g O
2. Convert to moles: 1
mol
25.9 g
= 1.85 mol N
14.01 g 1
mol
74.1 g
= 4.63 mol O
16.00 g

23. N1O2.5 N2O5 H. Empirical Formula
Find the empirical formula for a sample of 25.9% N and 74.1% O.
3. Divide by lowest number of moles:
1.85 mol N
4.63 mol O
= 1 N
= 2.5 O
1.85 mol
1.85 mol
N1O2.5
4. Multiply to get whole numbers (by 2 here)
N2O5

24. H. Empirical Formula
Find the empirical formula of a compound if a sample is 3.65 g sodium, 2.54 g sulfur, and 3.81 g oxygen.

25. CH3 C2H6 I. Molecular Formula
“True Formula” - the actual number of atoms in a compound
CH3
empirical
formula ?
C2H6
molecular
formula

26. (CH2)2  C2H4 empirical mass = 14.03 g/mol 28.1 g/mol 14.03 g/mol
I. Molecular Formula
The empirical formula for ethylene is CH2. Find the molecular formula if the molecular mass is g/mol?
empirical mass = g/mol
28.1 g/mol
14.03 g/mol
= 2.00
(CH2)2  C2H4

27. I. Molecular Formula
1. Find the empirical formula.
2. Find the empirical formula mass.
3. Divide the molecular mass by the empirical mass.
4. Multiply each subscript by the answer from step 3.

28. J. Molarity _________ Moles of solute dissolved in MOLARITY
Liters of solvent (concentration)
MOLARITY
n = number of moles
L = number of Liters
𝑀= 𝑛 𝐿
Unit is the MOLAR
How many moles of sodium fluoride are needed to make 400 ml of a 1.5 M solution   
What is the molarity of 35 g of calcium phosphate when dissolved in 800 ml of water?