Transcript 05-Nomenclature

Nomenclature
Naming
Compounds
Binary Compounds
Compounds with
only two elements
in any ratio
Naming
Binary
Compounds
Ionic
Compounds
Name positive element
(cation) first with its
normal name
Name negative element
(anion) last & change
its ending to -ide
KCl
CaCl2
Al2O3
Na2O
If the + element is not
from columns I or II
•its ox # must be
determined and written
in roman numerals
• FeO is Iron (II) Oxide
• Fe2O3 is Iron (III) Oxide
• CrO3 is Chromium (IV)Oxide
Determining the Charge
1) Add up the oxidation numbers of all
the negative elements
2) The positive portion must balance out
the negative portion
3) Divide the positive portion by the
metal subscript
CuCl
Fe2O3
MnO2
CrO3
Molecule
•A covalent compound
that can exist as a
separate unit
•Non-metals bond to
form molecules
Naming
Molecules or
Covalent
Compounds
•Same rules as ionic
compounds except:
• If two elements are from the same group,
lower element is first.
– SO2 is sulfur dioxide
• use geometric prefixes to determine the # of
each atom
Period 2 stopped here 9/8/06
Geometric Prefixes
1-mono
2-di
3-tri
4-tetra
5-penta
6-hexa
7-hepta
etc
CO
S2 O 3
N 2H4
SO3
Deriving Formulas
1) Write the symbol for each
element
2) Determine ox #s for each
3) Determine lowest common
multiple to balance the charge
4) Apply subscripts
Polyatomic
Ion
•A group of atoms
chemically
combined that
together have a
charge
Naming
Polyatomic
Ions
•Most are oxoanions
•A root element (most
are non-metals)
bound to oxygen
•Name the root element
•Change the ending
to -ate
-3
•PO4 = phosphate
•Some are unusual
Polyatomic Ion Endings
•Maximum O = -ate
•1 less than max O = -ite
-2
•SO4 = sulfate
-2
•SO3 = sulfite
Naming
Ternary
Compounds
Ternary Compounds
• Compounds containing
more than two different
elements
• Most contain polyatomic
ions
• Follow ionic rules for
naming the compound
• Name the polyatomic
ion as the positive or
negative portion
CaCO3
K2SO4
Pb(NO3)2
MgSO3
Naming
Acids
•Binary acids become:
•Hydro _____ ic acids
•HCl - Hydrochloric acid
• Ternary acids become:
• _____ ic acids or
• _____ ous acids
• H2SO4 - Sulfuric acid
• H2SO3 - Sulfurous acid
•____ ic acids form from
polyatomic ions ending
with ___ ate
•____ ous acids form from
polyatomic ions ending
with ___ ite
• ___ ide ions become:
• hydro ___ ic acids
• ___ ate ions become:
• ___ ic acids
• ___ ite ions become:
• ___ ous acids
Percent
Composition
by Mass
• Determine the atomic mass of
each element in the compound
• Determine the molecular mass
of the compound by adding
• Divide each elemental mass by
molecular mass
• Multiply by 100 %
MgCl2
• Mg = 24.3 g/mole
• 2 Cl = 2 x 35.5 = 71.0 g/mole
• MgCl2 = total = 95.3 g/mole
• % Mg =24.3/95.3 x 100%
• % Cl = 71.0/95.3 x 100 %
Determine %
Comp for Each:
Fe2O3
C3H6O3
CuSO4*5H2O
Empirical
Formula
•Lowest whole number
ratio of elements in a
compound
•C6H12O6: EF = CH2O
Determining
Empirical
formulas from
percent
composition
• Assume 100 g
• Change % directly to grams
• Use molar conversions to
convert grams to moles
• Divide each molar amount
by the smallest molar
amount
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Substance = 30 % O & 70 & Fe
30 % O --> 30 g O &
70 % Fe --> 70 g Fe
30/16 = 1.875 moles O
70 / 56 = 1.25 moles Fe
1.25/1.25 = 1 & 1.875/1.25 = 1.5
Ratio = 1.5 : 1 x 2 = 3 : 2
Empirical Formula Fe2O3
Find empirical for a
compound with:
70.0 % Fe
30.0 % O
Find empirical for a
compound with:
40 % Ca
12 % C
48 % O
Find empirical for a
compound with:
40.0 % C
6.7 % H
53.3 % O
Molecular
Formula
•The actual whole
number for each
element in the
compound
Molecular Formula
C6H12O6
Empirical Formula
CH2O
Solving MF from EF
1) Solve empirical mass
2) Divide EM into MM
3) Multiply EF by quotient
Name each of the following:
•KBr
•BaF2
•K2O
•Al2O3
MgS
K3P
LiH
H2S
Name each of the following:
FeO
Fe2O3
Name each of the following:
•CuO
•PbO2
•CrCl2
•CrCl3
MnS
Cu2O
MnF2
SnCl4
Name each of the following:
•SeO
•NO2
•N2O4
CS2
Cl2O
PCl3
Derive formulas for each:
• Cesium oxide
• Barium chloride
• Calcium phosphide
• Aluminum sulfide
Derive formulas for each:
• Lead(IV)oxide
• Copper(II)sulfide
• Manganese(VII)oxide
• Nickel(II)fluoride
Name each of the following:
•SO4
-3
•PO4
-1
•ClO4
-1
•ClO2
-2
-2
SO3
-1
NO3
-1
ClO3
-1
ClO
Derive formulas for each:
• Chromate
• Arsenate
• Arsenite
• Bromite
Name each of the following:
• BaCO2
• KNO2
• CuClO3
• Al2(SO4)3
Derive formulas for each:
• Potassium sulfate
• Lead(II)chromate
• Aluminum hydroxide
• Ammonium cyanide
Name each of the following:
• Cl2O
• N2O3
• CO2
• SO3
SO2
P2O5
CO
N2H4
Derive formulas for each:
• Silicon dioxide
• phosphorus trichloride
• Sulfur hexafluoride
• Iodine trifluoride
Name each of the following:
NH4Cl
KC2H3O2
KNO3
Li2CO3
BaSO4
K2HPO3
CuBrO
MgC2O4
Name each of the following:
HCl
H2S
HNO3
H2CO3
H2SO4
H3PO3
HBrO
HBrO4
Derive formulas for each:
•Chromic acid
•Hydroiodic acid
•Sulfurous acid
•Bromic acid
Name each of the following:
KCl
SO2
NaNO3
H2CO3(aq)
MnSO4
HI(aq)
HClO
NH4BrO4
Chapter 3 General
•Define all the Key
Terms on page 74
Nomenclature
•Work problems 43 – 56
•On Pages 51 & 52