Download Unit 6 Naming Binary Compounds

Unit 6
Chemical Nomenclature and Chemical
Reactions
Naming Binary Compounds
A binary compound is
  To
properly name the binary compound you
must first decide if it is ionic or covalent.
How do you determine this?
  The
binary compound must
Naming Binary Ionic Compounds - Type 1
1. The cation is always written first, then the anion.
2. Examine the cation, decide if it is a transition metal or
a main group metal.
3. If it is a main group metal, the binary compound is
Type 1.
  Charges
on Type 1 cations:
1 =
  Group
  Group
2 =
  Group
13 =
1
Naming Binary Ionic Compounds - Type 1
1. Name the cation first using the name of the
element.
2. Name the anion using the root of the element
name and adding - “ide” as the suffix.
  NaCl
-
  CaO
-
  AlN
-
Naming Binary Ionic Compounds - Type 2
1. Examine the cation, decide if it is a transition metal or
a main group metal.
2. If it is a transition metal, the binary compound is Type
2. Transition metals form multiple types of cations.
  Charges on Type
  Cu1+ , Cu2+
  Cr3+
,
  Mn2+,
2 cations:
Cr6+
Mn4+
Naming Binary Ionic Compounds - Type 2
1. Name the cation first using the name of the element.
2. Use the charge on the anion to determine the charge on
the cation, remembering that the overall charge of the
compound must be zero.
3. Add a Roman numeral after the cation to denote the
charge on the cation.
4. Name the anion using the root of the element name and
adding - “ide” as the suffix.
  TiO2   CuBr
-
  CrS3 -
2
Exceptions
 
Main group:
  Compounds
containing Pb, Sn, and Bi need
Roman numerials to indicate the charge on the
cation
 
Transition metals:
Zn, Ag, and Cd only form one type of cation. No
Roman numeral is necessary.
Naming Binary Covalent Compounds
Binary covalent compounds contain two types of
nonmetals bonded together, or a metalloid and a
nonmetal.
1. Name the elements in the order listed in the formula.
2. Use prefixes to indicate the number of each kind of
atom.
3. Omit the prefix mono- when the formula contains
only one atom of the first element in the name.
4. The suffix of the name of the second element is -ide.
Naming Binary Covalent Compounds Prefixes
3
Practice
1. CS2
2. IF7
3. B2O3
4. SiO4
5. H2O
Naming Ionic Compounds Containing
Polyatomic Ions
1. To name a compound containing a polyatomic ion, state the
cation first. You must determine if it is a main group metal or
transition metal and name the cation properly.
2. Then name the anion. Use the proper name of the
polyatomic ion.
 
Examples:
  NaClO
  AgNO2
  PbSO4
Writing Formulas from Names
For ionic Compounds:
1. Write the symbol of the cation and then the anion with
their respective charges. (For polyatomic ions you are
expected to know their charges and names.)
2. Add whatever subscripts are needed to balance the
charges, or criss-cross.
1. 
Calcium nitride -
2. 
Cobalt (III) chloride -
3. 
Iron (II) hydroxide -
4. 
Magnesium sulfate -
5. 
Lead (IV) sulfide -
4
Practice
Tin (II)
Naming Acids
An acid is a compound that contains one or more hydrogen
atoms and produces Ex: Naming Binary Acids – HCl
1. Identify the anion
Cl = 2. Name the anion with an –ic suffix
Cl- = 3. Add a hydro- prefix to the anion name
Add the word acid to the end
4. 
Tro's Introductory Chemistry, Chapter
5
15
5
Naming Oxyacids H2SO4
1. Identify the anion
SO4 = SO42- 2. If the anion has –ate suffix, change it to –ic. If the anion
has –ite suffix, change it to -ous
SO42- =
3. Write the name of the anion followed by the word acid
Tro's Introductory Chemistry, Chapter
5
16
Naming Oxyacids H2SO3
1. Identify the anion
SO3 = 2. If the anion has –ate suffix, change it to –ic. If
the anion has –ite suffix, change it to -ous
SO32- = 3. Write the name of the anion followed by the
word acid
Tro's Introductory Chemistry, Chapter
5
17
Practice
 
HI
 
HIO
 
HIO2
 
HIO3
 
HIO4
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Unit 6
Chemical Nomenclature and Chemical
Reactions
Chemical Equations
Chemical Reaction = process whereby one or more
reactants are changed into products
•  indicate
physical states: (s), (l), (g), (aq)
•  equation
must be balanced
•  matter
must be conserved (same number of each kind
of atom on reactant and product sides)
•  Charge
must be conserved (same overall charge)
•  only
change coefficients; never change subscripts to
balance an equation
Balancing Chemical Equations
Step 1
Write an unbalanced equation containing the correct formulas of the
reactants and products.
Step 2 Write the symbol for each element underneath the yield symbol.
Step 3
Write the number of each element present on the reactant side of the
equation in front of the element symbol. Write the number of
each element present on the product side of the equation behind
the element symbol.
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Balancing Chemical Equations
Step 4
Balance each element. Leave the elements that are present
in multiple compounds until the very end; they might
take care of themselves. Step 5
Verify that the number of atoms of each element is
balanced.
Examples
NH3(g) + O2(g)  NO(g) + H2O(g)
Examples
C7H14(g) + O2(g)  CO2(g) + H2O(g)
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Examples
 
Glass is sometimes decorated by etching patterns on its
surface. Etching occurs when hydrofluoric acid reacts with
silicon dioxide in the glass to form gaseous silicon
tetrafluoride and liquid water. Write and balance the
equation for this reaction.
Balancing Chemical Equations
Patterns of Chemical Reactions
Combination Reactions (Synthesis)
- Two or more substances react to form a single
product.
1. 
1. 
X + Y --> XY
2. 
2Na(s) + Cl2(g) --> 2NaCl (s) 9
Combination Reaction
Patterns of Chemical Reactions
2. Decomposition Reactions
- One substance decomposes to form two or more
products.
XY --> X + Y
2H2O (l) --> 2H2 (g) + O2(g) Decomposition Reaction
10
Patterns of Chemical Reactions
3. Combustion Reaction
A combustion reaction is a chemical change in
which an element or a compound reacts with
oxygen, often producing energy in the form of heat
and light.
CxHy + O2 -> CO2 + H2O +ENERGY!
Combustion Reaction
4. Single Replacement
 
One element displaces another in a compound
 
Type 1: element is a metal
  M + M’A → M’ + MA
  Cu(s) + 2 AgCl(aq) → 2 Ag(s) + CuCl2
 
Type 2: element is a halogen
  X2 + 2 BX’ → X’2 + BX
  Cl2 + 2 KBr → Br2 + 2 KCl
 
Use activity series to predict whether reaction “goes”
 
element + compound → element + compound
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Metal Activity Series
Metal
Ion(s)
Processes Used to
obtain the Metal
State of Metal
Li+
K+
Ca2+
Na+
Mg2+
Al3+
Pass electricity
through molten
mineral
(electrometallurgy)
Li(s)
K(s)
Ca(s)
Na(s)
Mg(s)
Al(s)
Manganese
Zinc
Chromium
Iron
Mn2+
Zn2+
Cr3+, Cr2+
Fe3+, Fe2+
Heat mineral with
charcoal or carbon
monoxide (CO)
(pyrometallurgy)
Mn(s)
Zn(s)
Cr(s)
Fe(s)
Lead
Copper
Mercury
Silver
Platinum
Gold
Pb2+
Cu2+, Cu+
Hg2+
Ag+
Pt2+
Au3+, Au+
Element
Lithium
Potassium
Calcium
Sodium
Magnesium
Aluminum
most
Active
Heat mineral in air
(pyrometallurgy) or
find the element free
least
active
Pb(s)
Cu(s)
Hg(s)
Ag(s)
Pt(s)
Au(s)
Trends in Metal Activity
 
A more reactive metal (higher in the activity
series) will cause ions of a less reactive metal
(lower in the activity series) to change to its
corresponding metal
Mg + ZnCl2 
Zn + MgCl2 
Mg + ZnCl2  MgCl2 + Zn
What are the charges on the metals?
Details:
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Oxidation of Cu(s) occurs with reduction of Ag+
(aq)
Cu(s)
Cu:
+ 2 Ag+(aq)

+ Ag+ + Ag+ 
Cu2+(aq) + 2 Ag(s)
Cu2+ + Ag
+ Ag
Cu is oxidized: it loses 2 electrons; Cu is the _____________
Ag+ is reduced: it gains 1 electrons; Ag+ is the ____________
Mnemonics for Oxidation/Reduction
OIL RIG:
LEO (the lion) says GER:
Terminology - Redox Reactions
 
OXIDATION —
 
REDUCTION —
 
OXIDIZING AGENT—electron acceptor; species is
reduced.
 
REDUCING AGENT—electron donor; species is
oxidized.
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Oxidation Numbers
 
An oxidation number is a positive or negative number
assigned to an atom to indicate its degree of oxidation or
reduction.
 
As a general rule, a bonded atom’s oxidation number is
the charge that it would have if the electrons in the bond
were assigned to the more electronegative element.
  Assign
an oxidation number to each Cr
atom.
K2CrO4
Cr2O3
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Single Replacement
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Patterns of Chemical Reactions
5. Double Replacement
- There is an interchange of partners between two compounds
AB + XY --> AY + XB
Pb(NO3)2 (aq) + K2CrO4 (aq) --> PbCrO4 (s) +2KNO3 (aq)  
The reaction proceeds only if one of the products is
insoluble in the reaction mixture
ZnBr2(aq) + 2 Ag(NO3)2(aq)
→ Zn(NO3)2(aq)
LiCl(aq) + Na2SO4(aq)
2 NaCl(aq) + Li2SO4(aq)
→
+ 2 AgBr(s)↓
Double Replacement
Predicting Whether a Reaction Will Occur
 
 
Keys to understanding spontaneous chemical
processes:
 
1. Energy spread. Reactions occur so that more stable
products are formed
 
2. Matter spread.
The most common “driving forces” that pull reactants
toward products are
  Formation of
  Formation of
  Transfer of electrons
  Formation of
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Practice
Classify each reaction as one of the four general types
a) 
Pt(s) + 2F2(g)  PtF4(l)
b) 
3Fe(s) + 4H2O(g) Fe3O4(s) + 4H2(g)
c) 
2H3BO3(s)  B2O3(s) + 3H2O(l)
d) 
BaCl2(aq) + Na2SO4(aq)  BaSO4(s) + 2NaCl (aq)
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