Naming

1
Naming Calculating Chemical Compounds

• Unit3 Lecture 2

2
Recap Bonding Occurs

• to fill the outer level of electrons of elements
• you can predict bonding by observing trends on
  the periodic table
• type of element metals, non metals, etc
• valence electrons for lewis diagrams
• oxidation criss-cross method

3
Counting Atoms

• A Chemical Formula shows how many of which atoms
  are in a molecule
• A Subscript is a number placed below and behind a
  symbol to show how many of which atoms are present

• H2O

4
Counting Atoms

• A Coefficient is placed in front of a molecule to
  show more than one molecule

• 3H2O

5
Counting Atoms

• H2 N2
• O2 F2
• I2 Cl2
• Br2

• A Diatomic Molecule shows two atoms of the same
  nonmetal (usually in gas form) that have bonded
  together
• Reactive nonmetals will bond with one another if
  no other substance is available for bonding

6
Polyatomic Ions

• A group of atoms that behave as one atom
• Keep together as a unit
• Listed on p. 619
• If more than one polyatomic ion is present in a
  molecule, parentheses set it apart
• Still use a subscript to show how many

• Ca(OH)2
• NH4Cl

7
Oxidation Numbers

• A positive or negative sign used to show what
  type of ion is formed after an atom has gained or
  lost enough electrons to be chemically stable
• Written like a charge sign (upper right)
• Always included with a list of polyatomic ions

8

• BASE OXIDATION NUMBERS BY GROUP
• 1 0
• 2 3 4 -3 -2 -1
• USE ROMAN NUMERALS

9
Oxidation s contd

• Transition metals have more than one oxidation
  number!!!!
• FeIII Fe3 Iron with 3 oxidation number
• FeII Fe2 Iron with 2 oxidation number
• MnII Mn2 Manganese with 2 oxidation
  number
• MnIII Mn3 Manganese with 3 oxidation
  number

10
Making Formulae the Criss-Cross Method

• cation first write element oxidation
• anion next write element oxidation
• without the or sign
• write the oxidation from one symbolon the
  other as a subscript
• remember to add parentheses aroundpolyatomic
  ions
• dont write the 1, it is implied
• reduce any evenly-divisible subscripts

11
Practice

• What is the correct formula for a bond between
• Carbon and Hydrogen?
• CH C2H2 CH3
• C2H3 CH4
• Sodium and Nitrogen?
• NaN Na2N2 Na3N
• Na2N3 Na3N4
• Calcium and Chlorine?
• CaCl Ca2Cl2 Ca2Cl
• CaCl2 Ca3Cl4

12
Practice contd

• What is the correct formula for a bond between
• Sodium and Hydroxide (OH) ? hint figure out
  the leftover charge from combining an oxygen an
  a hydrogen
• NaOH Na(OH)2 Na(OH)3
• Na2(OH)3 Na(OH)4
• Aluminum and Sulfate (SO4) ?
• AlSO4 Al2(SO4)2 Al2(SO4)3
• Al3(SO4)3 Al(SO4)4

13
Binomial Nomenclature

• Naming a two-part name
• Used to differentiate between Fluorine (an
  element) and Fluoride (part of a compound)
• Never change the name of a Polyatomic Ion
• Big difference between Sulfide and Sulfite

14
Naming Ionic Compounds

• List the positive ion (or metal) first
• Use Roman Numerals to show the Oxidation
  number of a transition metal
• Name the negative ion (or nonmetal), changing
  the ending to ide
• Oxide
• Sulfide
• Phosphide
• Ex FeO / Fe2O3
• Iron II Oxide / Iron III Oxide

15
Naming Polyatomic Compounds

• Compound is polyatomic if there are more than 2
  elements You will be given the names for common
  polyatomics.
• Still only 2 words in the name
• first term positive ion name
• second term negative ion name
• if second term is NOT a polyatomic, change
  ending to -ide
• if the second term is a negative polyatomic, do
  NOT change the ending

16
Naming Covalent Compounds

• Prefixes are used to show how many of which atoms
• number terms from Greek / Latin
• Write the name of the cation or most positive
• only add a prefix for the first atom if there is
  more than one
• Write the name of the anion or most negative
• add a prefix to tell how many are present
• change the ending to -ide

17
Covalent Compounds

• Prefixes are used to show how many of which atoms
• Prefixes are number-words from Greek Latin
• Write the name of the first atom
• Add a prefix only if there is more than one of
  the first
• Write the name of the second atom
• Add a prefix showing how many of the second are
  present
• Change the ending to -ide

18
Numbering Prefixes

• 1 Mono-
• 2 Di-
• 3 Tri-
• 4 Tetra-,
• 5 Penta-

• 6 Hexa-
• 7 Hepta-
• 8 Octa-
• 9 Nona-
• 10 Deka-

19
What is the name for N2O4?

1. Nitrogen Oxide
2. Dinitrogen Oxide
3. Dinitrogen Dioxide
4. Dinitrogen Tetraoxide
5. Nioxx (Nioxalate)

20
What is the name for Na2S?

1. Sodium Sulfide
2. Sodium Sulfite
3. Sodium Sulfate
4. Disodium Sulfide
5. Disodium Sulfate

21
What is the name for CO2?

1. Carbon Oxide
2. Carbon Dioxide
3. Monocarbon Oxide
4. Monocarbon Dioxide
5. Mi-Bref (B-hot)

22
What is the name for (NH4)2O?

1. Nitrogen Hydrogen Oxide
2. Mononitrogen Tetrahydrogen Oxide
3. Ammonium Oxide
4. Diammonium Oxide
5. Ammonium Oxalate

23
Practice

• What is the name for N2O4?
• non-metal non-metalso covalent
• Dinitrogen Tetraoxide
• What is the name for Na2S?
• metal non-metal ionic
• Sodium Sulfide
• What is the name for CO2?
• non-metal non-metal covalent
• Carbon Dioxide

24
Practice contd

• What is the name for (NH4)2O?hint you need to
  know what (NH4) is
• Nitrogen Hydrogen Oxide
• Mononitrogen Tetrahydrogen Oxide
• Ammonium Oxide
• Diammonium Oxide
• Ammonium Oxalate

CORRECT!!!!
25
Practice contd

• Al2S3
• CrO
• Lead (II) oxide
• PbO2
• (NH4)2S
• Ca(OH)2
• Iron (II) cyanide
• Fe(NO3)3
• Aluminum sulfide
• Chromium (II) oxide
• PbO
• Lead (IV) oxide
• Ammonium sulfide
• Calcium hydroxide
• Fe(CN)2
• Iron (III) nitrate