Precipitation Reactions and Net Ionic Equations - Questions

The Precipitation Reactions and Net Ionic Equations Concept Builder is comprised of 48 questions. The questions are divided into 16 different Question Groups and spread across three activities. Questions in the same group are rather similar to one another. The Concept Builder is coded to select at random a question from each group until a student is successful with that group of questions.

There are three activities in this Concept Builder. Those three activities are differentiated as follows:
 

• Soluble or Insoluble? Question Groups 1-6 ... Given three ionic compounds, identify all those that are soluble and insoluble.
• What's Going Down? Question Groups 7-12 ... Given the identity of two aqueous solutions that are being mixed, identify the chemical formula of the precipitate.
• Net Ionic Equations Question Groups 13-16 ... Given the identity of two aqueous solutions that are being mixed, identify the ions that will combine to precipitate and identify the net ionic equation for the precipitation reaction.

The questions from each group are shown below. Teachers are encouraged to view the questions in order to judge which activities are most appropriate for their classes. While the three activites have been designed to provide a scaffolded approach to writing net ionic equations, they can be done independent of each other.

The Physics Classroom grants teachers and other users the right to print these questions for private use. Users are also granted the right to copy the text and modify it for their own use. However, this document should not be uploaded to other servers for distribution to and/or display by others. The Physics Classroom website should remain the only website or server from which the document is distributed or displayed. We also provide a PDF that teachers can use under the same conditions. We have included a link to the PDF near the bottom of this page.

 

Precipitation Reactions and Net Ionic Equations

 
Activity 1: Soluble or Insoluble
Question Group 1
Question 1
The names of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
aluminum chloride
ammonium nitrate
zinc sulfide
 
 
Question 2
The names of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
aluminum nitrate
ammonium chloride
copper(II) sulfide
 
 
Question 3
The names of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
iron nitrate
iron(II) sulfide
potassium chloride
 
 
 
 
 
 
Question Group 2
Question 4
The names of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
calcium phosphate
copper(II) hydroxide
iron(II) nitrate
 
 
Question 5
The names of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
copper(II) nitrate
iron(II) phosphate
zinc hydroxide
 
 
Question 6
The names of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
calcium nitrate
copper(II) phosphate
iron(II) hydroxide
 
 
 
 
 
Question Group 3
Question 7
The names of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
barium sulfite
copper(II) acetate
tin(IV) carbonate
 
 
Question 8
The names of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
calcium sulfite
copper(II) carbonate
tin(IV) acetate
 
 
Question 9
The names of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
barium carbonate
iron(III) acetate
zinc sulfite
 
 
 
 
Question Group 4
Question 10
The names of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
ammonium sulfate
barium hydroxide
silver(I) chloride
 
 
Question 11
The names of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
ammonium bromide
barium sulfate
lead(II) chloride
 
 
Question 12
The names of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
ammonium carbonate
silver(I) chloride
strontium hydroxide
 
 
 
 
Question Group 5
Question 13
The formulae of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
AgCl
Ca(NO₃)₂
CuS
 
 
Question 14
The formulae of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
AgNO₃
BaCl₂
Mg(OH)₂
 
 
Question 15
The formulae of three ionic compounds are given below. Identify those that are soluble in water (i.e., dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
NaC₂H₃O₂
FeCO₃
Pb(NO₃)₂
 
 
 
 
 
 
Question Group 6
Question 16
The formulae of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
BaSO₄
FeS
NH₄C₂H₃O₂
 
 
Question 17
The formulae of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
KOH
ZnCl₂
ZnS
 
 
Question 18
The formulae of three ionic compounds are given below. Identify those that are insoluble in water (i.e., do NOT dissolve in water). Select all that apply. If necessary, view the list of Solubility Rules.
 
Cu(C₂H₃O₂)₂
CuS
Fe(OH)₂
 
 
 

 
Activity 2: What’s Going Down?
Question Group 7
Question 19
Aqueous solutions of NaOH and Cu(NO₃)₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
CuOH
Cu₂OH
Cu(OH)₂
NaNO₃
Na(NO₃)₂
Na₂NO₃
 
 
Question 20
Aqueous solutions of KOH and Mg(NO₃)₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
KNO₃
K(NO₃)₂
K₂NO₃
Mg(OH)₂
MgOH
Mg₂OH
 
 
Question 21
Aqueous solutions of LiOH and Ca(NO₃)₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
CaOH
Ca₂OH
Ca(OH)₂
LiNO₃
Li(NO₃)₂
Li₂NO₃
 
 
 
 
Question Group 8
Question 22
Aqueous solutions of Na₂SO₄ and BaCl₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
Ba₂SO₄
BaSO₄
Ba₄SO
NaCl
Na₂Cl₂
Na₂Cl₂
 
 
Question 23
Aqueous solutions of K₂SO₄ and Pb(NO₃)₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
KCl
K₂Cl₂
K₂Cl₂
PbSO₄
Pb₂SO₄
Pb₄SO
 
 
Question 24
Aqueous solutions of AgNO₃ and CaCl₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
AgCl
AgCl₂
Ag₂Cl
Ca(NO₃)₂
Ca₂NO₃
CaNO₃
 
 
 
 

 
Question Group 9
Question 25
Aqueous solutions of NH₄Cl and Pb(C₂H₃O₂)₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
NH₄(C₂H₃O₂)₂
NH₄C₂H₃O₂
NH(C₂H₃O₂)₂
PbCl
PbCl₂
Pb₄Cl
 
 
Question 26
Aqueous solutions of NH₄Br and Pb(NO₃)₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
NH₄(NO₃)₂
NH₄NO₃
NH(NO₃)₂
PbBr
PbBr₂
Pb₄Br
 
 
Question 27
Aqueous solutions of MgI₂ and Ag₂SO₄ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
AgI
AgI₂
AgI₄
MgSO₄
Mg₂SO₄
Mg(SO₄)₂
 
 
 

 
Question Group 10
Question 28
Aqueous solutions of Na₃PO₄ and FeCl₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
Fe₂(PO₄)₃
Fe₃PO₄
Fe₃(PO₄)₂
NaCl
NaCl₂
Na₃Cl₂
 
 
 
 
Question 29
Aqueous solutions of K₃PO₄ and CuCl₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
Cu₃PO₄
Cu₃(PO₄)₂
Cu₂(PO₄)₃
KCl
KCl₂
K₃Cl₂
 
 
 
Question 30
Aqueous solutions of Li₃PO₄ and MgCl₂ are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
LiCl
LiCl₂
Li₃Cl₂
Mg₃(PO₄)₂
Mg₂(PO₄)₃
Mg₃PO₄
 
 
 

 
Question Group 11
Question 31
Aqueous solutions of sodium carbonate and magnesium chloride are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
MgCl₂
MgCO₃
Mg(CO₃)₂
NaCl
Na₂CO₃
Mg₂CO₃
 
 
Question 32
Aqueous solutions of ammonium carbonate and calcium iodide are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
CaCO₃
Ca₃CO
Ca(CO₃)₂
NH₄I
NHI₄
(NH₄)₂I
 
 
Question 33
Aqueous solutions of potassium carbonate and copper(II) chloride are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
CuCO₃
Cu₂CO₃
Cu(CO₃)₂
KCl
K₂CO₃
KCO₃
 
 
 

 
Question Group 12
Question 34
Aqueous solutions of sodium sulfide and aluminum chloride are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
Al₂S
AlS₃
Al₂S₃
NaCl
NaS₂
Na₂S
 
 
Question 35
Aqueous solutions of ammonium sulfide and iron(III) chloride are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
Fe₂S
FeS₃
Fe₂S₃
NH₄Cl
NH₄S₂
(NH₄)₂S
 
 
Question 36
Aqueous solutions of magnesium sulfide and chromium(III) chloride are mixed and a precipitate is formed. What is the chemical formula of the precipitate? Use the list of Solubility Rules and the Polyatomic Ion list to help answer this question.
 
CrS₃
Cr₂S
Cr₂S₃
CrCl₃
MgS
Mg₂S
 
 
 
 
 
 

 
Activity 3: Net Ionic Equations
Question Group 13
Question 37
Aqueous solutions of sodium hydroxide and barium nitrate are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Ba⁺ _(aq)   +   OH^-_(aq)   →  BaOH_(s)
 
Ba²⁺ _(aq)   +   OH^-_(aq)   →  BaOH_(s)
 
Ba²⁺ _(aq)   +   2 OH^- _(aq)   →  Ba(OH)_{2 (s)}
 
4 Ba²⁺ _(aq)   +   2 OH^- _(aq)    →  Ba₄(OH)_{2 (s)}
 
2 Ba²⁺ _(aq)   +   OH^-_(aq)   →  Ba₂OH_(s)
 
 
 
Question 38
Aqueous solutions of potassium hydroxide and aluminum chloride are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Al³⁺ _(aq)   +   OH^-_(aq)   →  AlOH_(s)
 
Al⁺ _(aq)   +   OH^-_(aq)   →  AlOH_(s)
 
Al³⁺ _(aq)   +   3 OH^- _(aq)   →  Al(OH)_{3 (s)}
 
3 Al³⁺ _(aq)   +    OH^- _(aq)   →  3 Al₃OH_(s)
 
3 Al³⁺ _(aq)   +   2 OH^2- _(aq)   →  Al₃(OH)_{2 (s)}
 
 
 
 
Question 39
Aqueous solutions of ammonium hydroxide and calcium chloride are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Ca⁺ _(aq)   +   OH^-_(aq)    →   CaOH_(s)
 
 
Ca²⁺ _(aq)   +   OH^-_(aq)   →   CaOH_(s)
 
Ca²⁺ _(aq)   +   2 OH^- _(aq)   →   Ca(OH)_{2 (s)}
 
2 Ca²⁺ _(aq)   +   OH^-_(aq)    →  Ca₂OH_(s)
 
4 Ca²⁺ _(aq)   +   2 OH^-_(aq)   →  Ca₄(OH)_{2 (s)}
 
 
 
Question Group 14
Question 40
Aqueous solutions of sodium sulfide and aluminum chloride are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Al⁺ _(aq)   +   S^-_(aq)    →  AlS_(s)
 
Al³⁺ _(aq)   +   S^2-_(aq)    →  AlS_(s)
 
2 Al³⁺ _(aq)   +   3 S^2-_(aq)   →  Al₂S_{3 (s)}
 
2 Al⁺ _(aq)   +   S^2-_(aq)    →  Al₂S_(s)
 
3 Al³⁺ _(aq)   +   2 S^2-_(aq)   →  Al₃S_{2 (s)}
 
 
Question 41
Aqueous solutions of potassium sulfide and chromium(III) chloride are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation.
 
Cr³⁺ _(aq)   +   3 S^-_(aq)    →  CrS_{3 (s)}
 
Cr³⁺ _(aq)   +   S^2-_(aq)   →  Cr₂S_{3 (s)}
 
2 Cr³⁺ _(aq)   +   3 S^2- _(aq)   →  Cr₂S_{3 (s)}
 
2 Cr⁺ _(aq)   +   S^2-_(aq)    →  Cr₂S_(s)
 
3 Cr³⁺ _(aq)   +   2 S^2- _(aq)   →  Cr₃S_{2 (s)}
 
 
Question 42
Aqueous solutions of ammonium sulfide and iron(III) chloride are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Fe³⁺ _(aq)   +   S^2-_(aq)   →  Fe₂S_{3 (s)}
 
Fe³⁺ _(aq)   +   3 S^- _(aq)    →  FeS_{3 (s)}
 
2 Fe³⁺ _(aq)   +   3 S^2- _(aq)   →  Fe₂S_{3 (s)}
 
2 Fe⁺ _(aq)   +   S^2-_(aq)   →  Fe₂S_(s)
 
3 Fe³⁺ _(aq)   +   2 S^2- _(aq)   →  Fe₃S_{2 (s)}
 
 
 
 
Question Group 15
Question 43
Aqueous solutions of Na₂CO₃ and Fe(NO₃)₃ are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Fe³⁺ _(aq)   +   3 CO₃^- _(aq)   →  Fe(CO₃)_{3 (s)}
 
3 Fe⁺ _(aq)   +   CO₃^-_(aq)   →  Fe₃CO_{3 (s)}
 
2 Fe⁺ _(aq)   +   CO₃^2-_(aq)   →  Fe₂CO_{3 (s)}
 
2 Fe³⁺ _(aq)   +   3 CO₃^2- _(aq)   →  Fe₂(CO₃)_{3 (s)}
 
3 Fe³⁺ _(aq)   +   2 CO₃^2- _(aq)   →  Fe₃(CO₃)_{2 (s)}
 
 
 
Question 44
Aqueous solutions of (NH₄)₂CO₃ and AlCl₃ are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Al³⁺ _(aq)   +   3 CO₃^- _(aq)   →  Al(CO₃)_{3 (s)}
 
3 Al⁺ _(aq)   +   CO₃^-_(aq)   →  Al₃CO_{3 (s)}
 
2 Al⁺ _(aq)   +   CO₃^2-_(aq)   →  Al₂CO_{3 (s)}
 
2 Al³⁺ _(aq)   +   3 CO₃^2- _(aq)   →  Al₂(CO₃)_{3 (s)}
 
3 Al³⁺ _(aq)   +   2 CO₃^2- _(aq)   →  Al₃(CO₃)_{2 (s)}
 
 
 
Question 45
Aqueous solutions of K₂CO₃ and FeCl₃ are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Fe³⁺ _(aq)   +   3 CO₃^- _(aq)   →   Fe(CO₃)_{3 (s)}
 
2 Fe⁺ _(aq)   +   CO₃^2-_(aq)   →  Fe₂CO_{3 (s)}
 
2 Fe³⁺ _(aq)   +   3 CO₃^2- _(aq)   →   Fe₂(CO₃)_{3 (s)}
 
3 Fe⁺ _(aq)   +   CO₃^-_(aq)   →  Fe₃CO_{3 (s)}
 
3 Fe³⁺ _(aq)   +   2 CO₃^2- _(aq)   →  Fe₃(CO₃)_{2 (s)}
 
 
 
 
Question Group 16
Question 46
Aqueous solutions of Na₃PO₄ and CaCl₂ are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Ca²⁺ _(aq)   +   PO₄^3-_(aq)   →  CaPO_{4 (s)}
 
Ca²⁺ _(aq)   +   PO₄^3-_(aq)    →  Ca₃(PO₄)_{2 (s)}
 
2 Ca²⁺ _(aq)   +   3 PO₄^3-_(aq)    →  Ca₂(PO₄)_{3 (s)}
 
3 Ca⁺ _(aq)   +   PO₄^3-_(aq)   →  Ca₃PO_{4 (s)}
 
3 Ca²⁺ _(aq)   +   2 PO₄^3-_(aq)   →   Ca₃(PO₄)_{2 (s)}
 
 
Question 47
Aqueous solutions of K₃PO₄ and CuCl₂ are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Cu⁺ _(aq)   +   PO₄^3-_(aq)    →  Cu₃PO_{4 (s)}
 
Cu²⁺ _(aq)   +   PO₄^3-_(aq)   →  Cu₃(PO₄)_{2 (s)}
 
2 Cu²⁺ _(aq)   +   3 PO₄^3-_(aq)   →  Cu₂(PO₄)_{3 (s)}
 
3 Cu⁺ _(aq)   +   PO₄^3-_(aq)    →  Cu₃PO_{4 (s)}
 
 
3 Cu²⁺ _(aq)   +   2 PO₄^3-_(aq)    →  Cu₃(PO₄)_{2 (s)}
 
 
Question 48
Aqueous solutions of (NH₄)₃PO₄ and ZnCl₂ are mixed and a precipitate is formed. Determine the ions that precipitate and then identify the net ionic equation that describes its formation. 
 
Zn²⁺ _(aq)   +   PO₄^3-_(aq)   →  ZnPO_{4 (s)}
 
Zn²⁺ _(aq)   +   PO₄^3-_(aq)   →  Zn₃(PO₄)_{2 (s)}
 
2 Zn²⁺ _(aq)   +   3 PO₄^3-_(aq)   →  Zn₂(PO₄)_{3 (s)}
 
3 Zn⁺ _(aq)   +   PO₄^3-_(aq)   →  Zn₃PO_{4 (s)}
 
3 Zn²⁺ _(aq)   +   2 PO₄^3-_(aq)   →  Zn₃(PO₄)_{2 (s)}