Advanced Chemistry
Double Replacement Reactions
1) Know your solubility rules!!
EXAMPLE:
Solutions of potassium chromate and silver nitrate are mixed together.
Molecular EQN: K2CrO4(aq) + 2AgNO3(aq) ==> 2KNO3(aq) + Ag2CrO4(s)
Ionic EQN: K+(aq) + CrO42-(aq) + 2Ag+(aq) + NO3- (aq) ==> K+(aq) + NO3-(aq) +
Ag2CrO4(s)
Get rid of ions are written the same way on both sides. These are called spectator ions.
Net Ionic EQN: CrO42-(aq) + 2Ag+(aq) ==> Ag2CrO4(s)
When taking the AP test, they always want the net ionic equation.
Key words: Solutions, spectator ions and net ionic equation
On AP and IB tests, if it is a double replacement reaction, one of the products will
always precipitate.
For Each Problem, Write out the molecular, complete ionic, and net ionic equations and
answer the question that follows it.
1. Solutions of nickel(II) nitrate + cesium hydroxide
Q) Name the spectator ions.
2. Solutions of barium acetate and aluminum phosphate
Q) What is the name and the formula of the precipitate?
3. Aqueous solutions of lead (II) nitrate and sodium bromide are mixed
Q) Determine the molar mass of the precipitate.
4. Solutions of potassium phosphate plus calcium iodide.
Q) Calculate the molarity of the calcium iodide solution if 2.75 moles of the solid was mixed
with 225 mL of water.
6. Potassium sulfide solution is mixed with zinc acetate.
Q) If 25 mL of 2.0 M solution of potassium sulfide was mixed with 50.0 mL of 1.5 M zinc
acetate, what would be the concentration of the potassium ion after mixing?
Advanced Chemistry
Double Replacement Reactions
1) Know your solubility rules!!
EXAMPLE:
Solutions of potassium chromate and silver nitrate are mixed together.
Molecular EQN: K2CrO4(aq) + 2AgNO3(aq) ==> 2KNO3(aq) + Ag2CrO4(s)
Ionic EQN: K+(aq) + CrO42-(aq) + 2Ag+(aq) + NO3- (aq) ==> K+(aq) + NO3-(aq) +
Ag2CrO4(s)
Get rid of ions are written the same way on both sides. These are called spectator ions.
Net Ionic EQN: CrO42-(aq) + 2Ag+(aq) ==> Ag2CrO4(s)
When taking the AP test, they always want the net ionic equation.
Key words: Solutions, spectator ions and net ionic equation
On AP and IB tests, if it is a double replacement reaction, one of the products will
always precipitate.
For Each Problem, Write out the molecular, complete ionic, and net ionic equations and
answer the question that follows it.
1. Solutions of nickel(II) nitrate + cesium hydroxide
Q) Name the spectator ions.
2. Solutions of barium acetate and aluminum phosphate
Q) What is the name and the formula of the precipitate?
3. Aqueous solutions of lead (II) nitrate and sodium bromide are mixed
Q) Determine the molar mass of the precipitate.
4. Solutions of potassium phosphate plus calcium iodide.
Q) Calculate the molarity of the calcium iodide solution if 2.75 moles of the solid was mixed
with 225 mL of water.
6. Potassium sulfide solution is mixed with zinc acetate.
Q) If 25 mL of 2.0 M solution of potassium sulfide was mixed with 50.0 mL of 1.5 M zinc
acetate, what would be the concentration of the potassium ion after mixing?