Transcript I. Synthesis Reactions

Reaction Prediction
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What you MUST know before you even
begin trying to predict a reaction:
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Element names & symbols
Know your diatomics
Oxidation states for main group elements
Nomenclature rules for acids, ionic, & covalent
compounds.
– Balancing equations
– Interpreting word equations
I. Synthesis Reactions
A. Two elements produce a compound
Ag + O2 
C + O2 
S + O2 
B. Metal oxide + water produce a base (metallic
hydroxide)
Na2O + H2O 
C. Nonmetal oxide + water produce an oxyacid
SO2 + H2O 
D. Metal oxide + nonmetal oxide produce a salt (ionic
solid)
BaO + CO2 
CaO + SO2 
II. Decomposition
A. Reverse of synthesis reactions
NaCl + electricity 
B. Metallic chlorates produce metallic chlorides + O2
KClO3 
C. Metallic carbonates produce metallic oxides + CO2
ZnCO3 
D. Compound electrolyzed produce foundational
elements (may involve solute or water)
H2O + electricity 
E. Hydrated salts decompose into the salt and water.
Ex. Na2CO3 * H2O  Na2CO3 + H2O
Na2SO4 * 10 H2O 
Exceptions
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Hydrogen peroxide decomposes into
water and oxygen.
Sulfurous acid decomposes into water
and sulfur dioxide.
Carbonic acid decomposes into water
and carbon dioxide.
Ammonium hydroxide decomposes
into ammonia and water.
III. Single Replacement
A. Metal replaces metal ion in compound if metal is more
active (use activity series)
Al + CuSO4 
B. Metal replaces H in acids if metal is more active than
H in the compound
Zn + HCl 
C. Halogen replaces a halogen in compound if halogen
more active
Br2 + NaCl 
D. Very active metal replaces H in H2O; forms metallic
hydroxide & H2
K + H2O 
Ca + H2O 
Quick View of Solubility Rules
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All compounds containing alkali metal cations and the
ammonium ions are soluble – no exceptions.
All compounds containing nitrate, chlorate,
perchlorate, acetate, and bicarbonate anions are
soluble – no exceptions.
All chlorides, bromides, and iodides are soluble except
those containing Ag+, Pb2+, Hg2+, & Hg22+.
All sulfates are soluble except those containing Hg2+,
Pb2+, Sr, Ca, or Ba.
All hydroxides are insoluble except compounds of the
alkali metals, Ca, Sr, and Ba.
All compounds containing phosphate, sulfide
(exception alkaline metals of sulfides are soluble),
carbonate, and sulfite ions are insoluble except those
that also contain alkali metals or NH4+.
IV. Double Replacement:
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Two aqueous ionic compounds react if one
product is a precipitate, gas, or molecule (such
as water). Must know solubility rules & be able
to write net ionic equations.
K2CO3 + HNO3 
KOH + HI
K2CO3 + Ba(OH)2 
Fe2(SO4)3 + Ba(OH)2 
Hg2(NO3)2 + KI 
NH4I + AgNO3 
V. Combustion
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Oxygen (also termed as air in a problem) +
compound (usually a hydrocarbon) produce
oxides (usually carbon dioxide) of elements in
compound and water.
Complete and balance the reactions for the
combustion of the following compounds:
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CH4
C2H2
CH3OH
C6H12O6
C8H18
Additional Practice
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Use the Pre-AP Equation notes (word
document) for in depth explanations
and extra practice.
The answers may be checked using
the Pre-AP notes power point.
Study, Study, Study!!!!!!!