Principles of Chemistry

1
Principles of Chemistry
CHAPTER 5
NOMENCLATURE
2
Powerpoint Notes Available

• www.openchemistry.co.uk

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
3
Naming Compounds

• Common names - Traditional names for chemical
  compounds
• laughing gas, gypsum, Epsom salts, lead, sugar,
  table salt
• memorizing thousands of common names is not
  practical
• So chemists developed a simple naming system
• system focuses on rules and patterns rather than
  memorization

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
4
Binary Ionic Compounds

• Compounds composed of two elements. Two
  subcategories
• Metal and Nonmetal - binary ionic compound
• Metal and Metal
• Binary Ionic Compounds
• Positive ion (cation) - Always written first
• Negative ion (anion)

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
5
Binary Ionic Compounds

• Type I compounds
• Metals that only form one cation
• Example Na only forms Na never Na2 or Na3
• Type II compounds
• Metals can form two or more cations
• Example Iron forms two ions Fe3 and Fe2

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
6
Naming Type I Binary Compounds

• The cation is always named first and the anion
  second
• A simple cation (obtained from a single atom)
  takes its name from the name of the element. For
  example Mg2 is called magnesium
• A simple anion (obtained from a single atom) is
  named by taking the first part of the element
  name and adding -ide. Thus Cl- is called
  chloride
• chlor-ine - drop the ending, keep the root
• chlor-ide - add the suffix -ide to the root

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
7
Simple Cations and Anions
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
8
Naming Type I Binary Compounds

• The cation is always named first and the anion
  second

AlCl3
Aluminum and Chlorine atoms
Al3
Cl-

Cl-
?
AlCl3
Cl-
(3) (1-) (1-) (1-) 0
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
9
Naming Type I Binary Compounds

• A simple cation (obtained from a single atom)
  takes its name from the name of the element. For
  example Mg2 is called magnesium

AlCl3
Aluminum and Chlorine atoms
Al3
Cl-

Cl-
?
AlCl3
Cl-
(3) (1-) (1-) (1-) 0
NAME Aluminum ________________
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
10
Naming Type I Binary Compounds

• A simple anion (obtained from a single atom) is
  named by taking the first part of the element
  name and adding -ide. Thus Cl- is called
  chloride
• chlor-ine - drop the ending, keep the root
• chlor-ide - add the suffix -ide to the root

Al3
Cl-

Cl-
?
AlCl3
Cl-
NAME Aluminum Chloride
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
11
Type II Ionic Compounds

• Type II Compounds can form two or more cations
• Practical situation Gold Chloride

Au3
Cl-

Cl-
?
AuCl3
Cl-
(3) (1-) (1-) (1-) 0
Au

?
AuCl
Cl-
(1) (1-) 0
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
12
Naming Type II Compounds

• The cation is always named first and the anion
  second
• Because the cation can assume more than one
  charge, the cation charge is specified by a Roman
  numeral in parentheses

Au3
Cl-

Cl-
?
AuCl3
Cl-
Gold(III) Choride
Au

?
AuCl
Cl-
Gold(I) Choride
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
13
Type II cations
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
14
Principle of Charge Balance

• SnCl2 contains two Cl- anions, so the charge of
  Sn is what?

Snx
Cl-

?
SnCl2
Cl-
(X) (1-) (1-) 0
(X) 2
Sn2

?
SnCl2
Cl-
Cl-
In this case, tin has a 2 charge
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
15
Rules for Binary Compounds that contains only
Nonmetals

• The first element in the formula is named first,
  and the full element name is used
• The second element is named as though it were an
  anion
• Prefixes are used to denote the numbers of atoms
  present. (listed on the next slide)
• The prefix mono- is never used for naming the
  first element.

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
16
Numerical Prefixes
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
17
Review The Nonmetals
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
18
Naming Type III Binary Compounds

• The second element is named as though it were an
  anion

BF3
Boron and Fluorine
B3
F-

F-
?
BF3
F-
(3) (1-) (1-) (1-) 0
NAME Boron ________________
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
19
Naming Type III Binary Compounds

• The first element in the formula is named first,
  and the full element name is used
• Prefixes are used to denote the numbers of atoms
  present. (listed on the next slide)

B3
F-

F-
?
BF3
F-
(3) (1-) (1-) (1-) 0
NAME Boron trifluoride (Tri-fluor-ide)
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
20
Organizational Summery Binary Compounds
Binary Compound?
Yes
Metal Present?
no
Yes
Type III prefixes
Metal form multiple cations?
no
yes
Type I prefixes
Type II prefixes
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
21
Polyatomic Ionic Compounds

• Polyatomic ions - Charged entities composed of
  several atoms bound together
• Assigned special names you must memorize
• Oxyanions - Several series of polyatomic anions
  exist that contain an atom of a given element and
  different numbers of oxygen atoms

-
chlorate
hypochlorite
-




O
O
O
Cl
perchlorate
-
Cl


O
-
chlorite
O
O


Cl
O
O
Cl
O
O
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
22
Oxyanions
sulfite
sulfate
2-
2-




O
O
O
O
N
Cl
O
O
O
-ate
-ite
hypo-____-ite
per-____-ate
(fewer Oxygens) Relative Number of Oxygens
(more Oxygens)
-
chlorate
hypochlorite
-




O
O
O
Cl
perchlorate
-
Cl


O
-
chlorite
O
O


Cl
O
O
Cl
O
O
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
23
Common Polyatomic Ions
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
24
Naming Polyatomic Compounds

• Naming is very similar to naming binary ionic
  compounds
• you must learn to recognize the polyatomic ions
• Examples
• NaOH - Sodium Hydroxide
• Fe(NO3)3 - Iron(III) Nitrate
• Na2SO3 - Sodium Sulfite

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
25
Naming Acids

• If the anion does not contain oxygen, the acid
  is named with the prefix hydro- and the suffix
  -ic attached to the root for the element.
• HCl - Hydrochloric acid
• H2S - hydrosulfuric acid
• When the anion contains oxygen, the acid name is
  formed from the root name of the central element
  of the anion or the anion name, with a suffix
  -ic or -ous

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
26
Naming Acids Containing Oxygen

• When the anion name ends in -ate, the suffix -ic
  is used
• H2SO4, SO42- (sulfate anion) - sulfuric acid
• H3PO4, PO43- (phosphate anion) - phosphoric acid
• When the anion name ends in -ite, the suffix -ous
  is used
• H2SO3, SO32- (sulfite anion) - sulfurous acid

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
27
Naming Acids Containing Oxygen
-ic
-ous
hypo-____-ous
per-____-ic
(fewer Oxygens) Relative Number of Oxygens
(more Oxygens)
-
hypochlorous acid
chloric acid
-




O
O
O
Cl
perchloric acid
-
Cl
H
H


O
-
chlorous acid
O
O


Cl
H
O
O
Cl
O
O
H
This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License
28
References

• Zumdahl, Steven. DeCoste, Donald. Introductory
  Chemistry A foundation. Sixth Edition. Houghton
  Mifflin Company. ISBN 0-618-80327.
• Wikipedia (some graphics)

This work by Justin Zollars is licensed under a
Creative Commons Attribution 3.0 License