predicting the products of double replacement reactions
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Predicting the Products of Double Replacement Reactions. Using a Solubility Table. Introduction. Double replacement reactions are reactions that occur in solution. Cations and anions change places in double replacement reactions. One product must be: solid (precipitate) insoluble gas - PowerPoint PPT PresentationTRANSCRIPT
Predicting the Products of Double
Replacement Reactions
Using a Solubility Table
Introduction Double replacement reactions are reactions
that occur in solution. Cations and anions change places in double
replacement reactions. One product must be:
solid (precipitate) insoluble gas water
Basics Double replacement reactions have the
following form:
AX(aq) + BY(aq) → AY(s) + BX(aq) For example:
BaCl2(aq) + Na2SO4(aq) → BaSO4(s) + 2 NaCl(aq)
Pb(NO3)2(aq) + 2 HCl(aq) → PbCl2(s) + 2 HNO3(aq)
KOH(aq) + HBr(aq) → H2O(l) + KBr(aq)
Basics In each of these reactions, the cations and
anions change partners:
BaCl2(aq) + Na2SO4(aq) → BaSO4(s) + 2 NaCl(aq)
Basics In each of these reactions, the cations and
anions change partners:
BaCl2(aq) + Na2SO4(aq) → BaSO4(s) + 2 NaCl(aq)
Basics In each of these reactions, the cations and
anions change partners:
BaCl2(aq) + Na2SO4(aq) → BaSO4(s) + 2 NaCl(aq)
Basics Again, one of the products must be:
a precipitate (indicated by (s) or ↓) an insoluble gas (indicated by (g) or ↑) water (from the reaction of an acid with a
base)
We will be looking at those reactions which form (or don’t form) precipitates as products
Solubility Solubility is the ability of a compound, called
the solute, to dissolve in a liquid, called the solvent.
Different compounds have different solubilities.
We are interested in those compounds that are not very soluble.
We want to know which ones form precipitates.
Solubility We have a set of guidelines for the solubility
of ionic compounds in water. The guidelines tell us whether or not a
particular family of ionic compounds is soluble.
We can use these guidelines to predict the formation of a participate in a potential double replacement reaction.
If no precipitate forms, then there is no reaction.
Solubility Guidelines1. Most sodium, Na+, potassium, K+, and ammonium, NH4
+, compounds are soluble in water.
2. Most nitrate, NO3−, acetate, CH3COO−, and chlorate, ClO3
−, compounds are soluble in water.
3. Most chloride, Cl−, compounds are soluble, except those of silver, AgCl, mercury(I), Hg2Cl2, and lead, PbCl2. Lead(II) chloride is soluble in hot water.
4. Most sulfate, SO42−, compounds are soluble, except those of
barium, BaSO4, strontium, SrSO4, and lead, PbSO4.5. Most carbonate, CO3
2−, phosphate, PO43−, and silicate, SiO3
2−, compounds are insoluble, except those of sodium, potassium, and ammonium.
6. Most sulfides, S2−, compounds are insoluble, except those of calcium, Ca2+, strontium, Sr2+, sodium, Na+, potassium, K+, and ammonium, NH4
+.
Example 1.
Predict the result of mixing a solution of lead(II) nitrate with sodium sulfate.
Pb(NO3)2(aq) + Na2SO4(aq)
Cations Anions Possible precipitatesPb2+ NO3
–
Na+ SO42–
Na2SO4
Pb(NO3)2
Applications
PbSO4
NaNO3 We know that two of the possible precipitates are soluble.
These are already in solution.
Na2SO4
Pb(NO3)2
NaNO3NaNO3
Example 1.
Predict the result of mixing a solution of lead(II) nitrate with sodium sulfate.
Pb(NO3)2(aq) + Na2SO4(aq)
Cations Anions Possible precipitatesPb2+ NO3
–
Na+ SO42–
Na2SO4
Pb(NO3)2
Applications
PbSO4
1. Most Na+, K+, and NH4
+ compounds are soluble in water.
Next, we look at the solubility guidelines
Example 1.
Predict the result of mixing a solution of lead(II) nitrate with sodium sulfate.
Pb(NO3)2(aq) + Na2SO4(aq)
Cations Anions Possible precipitatesPb2+ NO3
–
Na+ SO42–
NaNO3
Na2SO4
Pb(NO3)2
Applications
PbSO4
2. Most NO3–, CH3COO–,
and ClO3–
compounds are soluble in water.
Next, we look at the solubility guidelines
Example 1.
Predict the result of mixing a solution of lead(II) nitrate with sodium sulfate.
Pb(NO3)2(aq) + Na2SO4(aq)
Cations Anions Possible precipitatesPb2+ NO3
–
Na+ SO42–
NaNO3
Na2SO4
Pb(NO3)2
Applications
PbSO4
3. Most Cl– compounds are soluble, except those of Ag+, Hg2
2+, and Pb2+.
Next, we look at the solubility guidelines
Example 1.
Predict the result of mixing a solution of lead(II) nitrate with sodium sulfate.
Pb(NO3)2(aq) + Na2SO4(aq)
Cations Anions Possible precipitatesPb2+ NO3
–
Na+ SO42–
NaNO3
Na2SO4
Pb(NO3)2
Applications
PbSO4
4. Most SO42–
compounds are soluble, except those of Ba2+, Sr2+, and Pb2+.
Next, we look at the solubility guidelines
Example 1.
Predict the result of mixing a solution of lead(II) nitrate with sodium sulfate.
Pb(NO3)2(aq) + Na2SO4(aq)
Cations Anions Possible precipitatesPb2+ NO3
–
Na+ SO42–
NaNO3
Na2SO4
Pb(NO3)2
Applications
PbSO4
PbSO4 will be a precipitate.
Next, we look at the solubility guidelines
Example 1.
Predict the result of mixing a solution of lead(II) nitrate with sodium sulfate.
Pb(NO3)2(aq) + Na2SO4(aq)
Cations Anions Possible precipitatesPb2+ NO3
–
Na+ SO42–
NaNO3
Na2SO4
Pb(NO3)2
Applications
PbSO4
PbSO4 will be a precipitate.
We now complete the equation.
Example 1.
Predict the result of mixing a solution of lead(II) nitrate with sodium sulfate.
Pb(NO3)2(aq) + Na2SO4(aq) → PbSO4(s) + 2 NaNO3(aq)
Cations Anions Possible precipitatesPb2+ NO3
–
Na+ SO42–
NaNO3
Na2SO4
Pb(NO3)2
Applications
PbSO4
PbSO4 will be a precipitate.
We now complete the equation.
Example 2.
Predict the result of mixing a solution of copper(II) nitrate with sodium chloride.
Cu(NO3)2(aq) + NaCl (aq)
Cations Anions Possible precipitatesCu2+ NO3
–
Na+ Cl– CuCl2NaClNaCl
Cu(NO3)2Cu(NO3)2
Applications
NaNO3 We know that two of the possible precipitates are soluble.
These are already in solution.
Example 2.
Predict the result of mixing a solution of copper(II) nitrate with sodium chloride.
Cu(NO3)2(aq) + NaCl (aq)
Cations Anions Possible precipitatesCu2+ NO3
–
Na+ Cl– CuCl2NaClNaCl
Cu(NO3)2Cu(NO3)2
Applications
NaNO31. Most Na+, K+, and
NH4+ compounds
are soluble in water.
Next, we look at the solubility guidelines
NaNO3
Example 2.
Predict the result of mixing a solution of copper(II) nitrate with sodium chloride.
Cu(NO3)2(aq) + NaCl (aq)
Cations Anions Possible precipitatesCu2+ NO3
–
Na+ Cl– CuCl2NaClNaCl
Cu(NO3)2Cu(NO3)2
Applications
NaNO3
Next, we look at the solubility guidelines
2. Most NO3–, CH3COO–,
and ClO3–
compounds are soluble in water.
Example 2.
Predict the result of mixing a solution of copper(II) nitrate with sodium chloride.
Cu(NO3)2(aq) + NaCl (aq)
Cations Anions Possible precipitatesCu2+ NO3
–
Na+ Cl– CuCl2NaClNaCl
Cu(NO3)2Cu(NO3)2
Applications
NaNO3
Next, we look at the solubility guidelines
3. Most Cl– compounds are soluble, except those of Ag+, Hg2
2+, and Pb2+.
CuCl2
Example 2.
Predict the result of mixing a solution of copper(II) nitrate with sodium chloride.
Cu(NO3)2(aq) + NaCl (aq)
Cations Anions Possible precipitatesCu2+ NO3
–
Na+ Cl– CuCl2NaClNaCl
Cu(NO3)2Cu(NO3)2
Applications
NaNO3
Next, we look at the solubility guidelines
CuCl2There is no precipitate and no reaction.
Example 2.
Predict the result of mixing a solution of copper(II) nitrate with sodium chloride.
Cu(NO3)2(aq) + NaCl (aq)
Cations Anions Possible precipitatesCu2+ NO3
–
Na+ Cl– CuCl2NaClNaCl
Cu(NO3)2Cu(NO3)2
Applications
NaNO3
CuCl2There is no precipitate and no reaction.
We now complete the equation.
Example 2.
Predict the result of mixing a solution of copper(II) nitrate with sodium chloride.
Cu(NO3)2(aq) + NaCl (aq) → no reaction
Cations Anions Possible precipitatesCu2+ NO3
–
Na+ Cl– CuCl2NaClNaCl
Cu(NO3)2Cu(NO3)2
Applications
NaNO3
CuCl2There is no precipitate and no reaction.
We now complete the equation.
Predict the result of mixing each of the following solutions.
1. AgNO3(aq) + NaCl(aq) →
2. Cu2SO4(aq) + Na2CO3(aq) →
3. BaCl2(aq) + CuSO4(aq) →
4. Pb(CH3COO)2(aq) + Na3ClO3(aq) →
5. FeCl2(aq) + CaS(aq) →
Practice Problems
AgCl(s) + NaNO3(aq)
CuCO3(s) + Na2SO4(aq)
BaSO4(s) + CuCl2(aq)
no reactionFeS(s) + CaCl2(aq)