Double Replacement Reactions

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Double Replacement Reactions
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Double replacement reactions occur when the metal
ions of two aqueous compounds switch places.
Precipitates (solids) often form as a
result. M1B M2Y ? M1Y M2B (Metal 1
switches with Metal 2) Examples
AgNO3(aq) NaCl (aq) ? AgCl (s)
NaNO3 (aq) Ag Cl-
Na NO3-
This is the precipitate.
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Double replacement reactions occur when the metal
ions of two aqueous compounds switch places.
Precipitates (solids) often form as a
result. M1B M2Y ? M1Y M2B (Metal 1
switches with Metal 2) Examples
AgNO3(aq) NaCl (aq) ?
Ag Cl- Na NO3-
4
Double replacement reactions occur when the metal
ions of two aqueous compounds switch places.
Precipitates (solids) often form as a
result. M1B M2Y ? M1Y M2B (Metal 1
switches with Metal 2) Examples
AgNO3(aq) NaCl (aq) ?
Ag Cl- Na NO3- One or
two of the new combinations must have low
solubility to get a reaction! Low solubility
means that a precipitate or solid will
form.
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Precipitates form because they have low
solubility in water. Need to use the Solubility
Table to determine the precipitate.
AgCl is the precipitate because it has low
solubility in water.
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Precipitates form because they have low
solubility in water. Need to use the Solubility
Table to determine the precipitate.
AgCl is the precipitate because it has low
solubility in water.
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Double replacement reactions occur when the metal
ions of two aqueous compounds switch places.
Precipitates (solids) often form as a
result. M1B M2Y ? M1Y M2B (Metal 1
switches with Metal 2) Examples
AgNO3(aq) NaCl (aq) ?
Ag Cl- Na NO3-
This is the precipitate Low Solubility
8
Double replacement reactions occur when the metal
ions of two aqueous compounds switch places.
Precipitates (solids) often form as a
result. M1B M2Y ? M1Y M2B (Metal 1
switches with Metal 2) Examples
AgNO3(aq) NaCl (aq) ? AgCl (s)
NaNO3 (aq) low
solubility high solubility (s)
(aq)
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• Examples
• Sr(OH)2(aq) Mg(NO3)2 (aq) ?
• Sr2 NO3-
  Mg2 OH-
• NO3-
  OH-
• Mg(OH)2 is the
  precipitate.

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• Examples
• Sr(OH)2(aq) Mg(NO3)2 (aq) ?
• Sr2 NO3-
  Mg2 OH-
• NO3-
  OH-
• Mg(OH)2 is the
  precipitate.

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• Examples
• Sr(OH)2(aq) Mg(NO3)2 (aq) ? Sr(NO3)2
  Mg(OH)2
• Sr2 NO3-
  Mg2 OH-
• NO3-
  OH-
• Mg(OH)2 is the
  precipitate.

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• Examples
• Sr(OH)2(aq) Mg(NO3)2 (aq) ? Sr(NO3)2
  Mg(OH)2
• Sr2 NO3-
  Mg2 OH-
• NO3-
  OH-
• Mg(OH)2 is the
  precipitate.

Mg2
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• Examples
• Sr(OH)2(aq) Mg(NO3)2 (aq) ? Sr(NO3)2
  (aq) Mg(OH)2(s)
• Sr2 NO3-
  Mg2 OH-
• NO3-
  OH-
• Mg(OH)2 is low solubility (s)
• Sr(NO3)2 is high solubility (aq)

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• Predict and balance the following DR reactions.
  Include all phase
• symbols. Use your solubility table to identify
  the precipitate.
• Sulphuric acid Calcium phosphate
• H2SO4(aq) Ca(NO3)2(aq) ?
• Magesium chloride Sodium sulphate
• MgCl2(aq) Na2SO4(aq) ?
• 3. Cobalt (II) nitrate Sodium carbonate
  
• Co(NO3)2(aq) Na2CO3(aq) ?

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• Predict and balance the following DR reactions.
  Include all phase
• symbols. Use your solubility table to identify
  the precipitate.
• Sulphuric acid Calcium phosphate
• H2SO4(aq) Ca(NO3)2(aq) ? CaSO4(s)
  2HNO3(aq)
• low high
• Magesium chloride Sodium sulphate
• MgCl2(aq) Na2SO4(aq) ?
• 3. Cobalt (II) nitrate Sodium carbonate
  
• Co(NO3)2(aq) Na2CO3(aq) ?

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• Predict and balance the following DR reactions.
  Include all phase
• symbols. Use your solubility table to identify
  the precipitate.
• Sulphuric acid Calcium phosphate
• H2SO4(aq) Ca(NO3)2(aq) ? CaSO4(s)
  2HNO3(aq)
• low high Magesium chloride
  Sodium sulphate
• MgCl2(aq) Na2SO4(aq) ?
• 3. Cobalt (II) nitrate Sodium carbonate
  
• Co(NO3)2(aq) Na2CO3(aq) ?

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• Predict and balance the following DR reactions.
  Include all phase
• symbols. Use your solubility table to identify
  the precipitate.
• Sulphuric acid Calcium phosphate
• H2SO4(aq) Ca(NO3)2(aq) ? CaSO4(s)
  2HNO3(aq)
• low high
• Magesium chloride Sodium sulphate
• MgCl2(aq) Na2SO4(aq) ? No reaction
• Both are highly soluble! Need one
  low!
• Cobalt (II) nitrate Sodium carbonate
  
• Co(NO3)2(aq) Na2CO3(aq) ?

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• Predict and balance the following DR reactions.
  Include all phase
• symbols. Use your solubility table to identify
  the precipitate.
• Sulphuric acid Calcium phosphate
• H2SO4(aq) Ca(NO3)2(aq) ? CaSO4(s)
  2HNO3(aq)
• low high
• Magesium chloride Sodium sulphate
• MgCl2(aq) Na2SO4(aq) ? No reaction
• Both are highly soluble! Need one
  low!
• Cobalt (II) nitrate Sodium carbonate
  
• Co(NO3)2(aq) Na2CO3(aq) ? CoCO3(s)
  2NaNO3 (aq) low high

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Acid-Base Neutralization reactions are a special
type of Double replacement reaction. Acid
Base ? Salt Water HCl(aq)
NaOH(aq) ? NaCl(aq) HOH(l) When water or a
solid is produced a DR reaction occurs. Acid
carbonate reactions are another type of DR
reaction. These types of reactions form aqueous
carbonic acid which immediately breaks down to
form carbon dioxide and water. 2HNO3(aq)
Na2CO3(aq) ? 2NaNO3(aq) H2CO3(aq) 2HNO3(aq)
Na2CO3(aq) ? 2NaNO3(aq) H2O(l) CO2(g) A
double replacement reaction happens when a solid,
gas, or water is produced.