Chem 1212 final Exam Questions and Answers| New Update with 100% Correct Answers
Match the confirmation test with a description of the positive results.
Confirmation test for Mn2+: a purple solution
Match the confirmation test with a description of the positive results.
Confirmation test for Cr3+: a pale yellow tan solid
Match the confirmation test with a description of the positive results.
Confirmation test for Ni2+: a red pink precipitate
Match the confirmation test with a description of the positive results.
Confirmation test for Fe3+: dark blood red solution
Match the confirmation test with a description of the positive results.
Confirmation test for Zn2+: gray-white precipitate
You have one test tube which contains a solution that is either Ni+2(aq) or Cr+3(aq). Select a
reagent that will allow you to differentiate between the two chemical species. If the solution is
Ni+2(aq), what will happen when the reagent is added? If the solution is Cr+3(aq) what will
happen when the reagent is added? NaOH
If it is Ni2+, the solution will remain the same after adding the NaOH.
If it is Cr3+, a green precipitate will form after adding the NaOH.
You have one test tube which contains a solution that is either Ni+2(aq) or Fe+3(aq). Select a
reagent that will allow you to differentiate between the two chemical species. If the solution is
Ni+2(aq), what will happen when the reagent is added? If the solution is Fe+3(aq) what will
happen when the reagent is added? KSCN
If it is Ni2+, the green solution will stay the same after adding the KSCN.
If it is Fe3+, the blood red solution will form after adding the KSCN.
,the liquid that was carefully poured into a new container decantate
To carfully pour a liquid into another conatiner decant
name the chemical: K2CrO4 potassium chromate
You have two test tubes. One test tube contains Ag+(aq) solution and the other test tube
contains Bi+3(aq). Predict what will happen when HCl(aq) is added to both test tubes. If a
reaction occurs, what is the new chemical formula? Ag+ will form a white precipitate, AgCl.
Bi3+ will remain unchanged.
You have two test tubes. One test tube contains Pb+2(aq) solution and the other test tube
contains Bi+3(aq). Predict what will happen when HCl(aq) is added to both test tubes. If a
reaction occurs, what is the new chemical formula? Pb+2(aq) will form a white precipitate,
PbCl2(s). Bi+3(aq) will remain unchanged.
You have two test tubes. One test tube contains Pb+2(aq) solution and the other test tube
contains Cu+2(aq). Predict what will happen when HCl(aq) is added to both test tubes. If a
reaction occurs, what is the new chemical formula? Pb+2(aq) will form a white precipitate,
PbCl2(s). Cu+2(aq) will remain unchanged.
Which of the chemicals are oxidants? K2CrO4
The liquid above the solid in a mixture of solid and solution supernate
A solid compound that forms as a result of mixing reagents together in a solution precipitate
, A unique chemical used in this experiment is K4Fe(CN)6(aq). What is its name? potassium
ferrocyanide
NH3(aq) and NH4OH(aq) are different ways of writing the chemical formula of the which
chemical? aqueous ammonia
Select the steps that will compose a rationale for the cation Ni+2 being absent in an unknown.
A red-pink solid did not form after the addition of H2DMG in step 3-F.
Select the step(s) that will compose a rationale for the cation Ni+2 being present in an unknown
A precipitate formed when 6 M NaOH was added to the unknown solution in step 3-A
The precipitate from step 3-A dissolved in 6 M HNO3.
A strawberry red precipitate formed in step 3-F
Separation can be achieved when a reaction occurs in a mixture. The resulting mixture will have
one chemical species in a solution and the other chemical species as a solid. The mixture is
centrifuged and the supernate is decanted into a separate test tube. Now the solid and solution
are separated from each other.
What reagent could you add to a mixture of Ag+ and Cu+2 to separate the two species? HCl
Separation can be achieved when a reaction occurs in a mixture. The resulting mixture will have
one chemical species in a solution and the other chemical species as a solid. The mixture is
centrifuged and the supernate is decanted into a separate test tube. Now the solid and solution
are separated from each other.
What reagent could you add to a mixture of Pb+2 and Bi+3 to separate the two species? HCl
Separation can be achieved when a reaction occurs in a mixture. The resulting mixture will have
one chemical species in a solution and the other chemical species as a solid. The mixture is
centrifuged and the supernate is decanted into a separate test tube. Now the solid and solution
are separated from each other. What reagent could you add to a mixture of Cu+2 and Bi+3 to
separate the two species? NH3
Match the confirmation test with a description of the positive results.
Confirmation test for Mn2+: a purple solution
Match the confirmation test with a description of the positive results.
Confirmation test for Cr3+: a pale yellow tan solid
Match the confirmation test with a description of the positive results.
Confirmation test for Ni2+: a red pink precipitate
Match the confirmation test with a description of the positive results.
Confirmation test for Fe3+: dark blood red solution
Match the confirmation test with a description of the positive results.
Confirmation test for Zn2+: gray-white precipitate
You have one test tube which contains a solution that is either Ni+2(aq) or Cr+3(aq). Select a
reagent that will allow you to differentiate between the two chemical species. If the solution is
Ni+2(aq), what will happen when the reagent is added? If the solution is Cr+3(aq) what will
happen when the reagent is added? NaOH
If it is Ni2+, the solution will remain the same after adding the NaOH.
If it is Cr3+, a green precipitate will form after adding the NaOH.
You have one test tube which contains a solution that is either Ni+2(aq) or Fe+3(aq). Select a
reagent that will allow you to differentiate between the two chemical species. If the solution is
Ni+2(aq), what will happen when the reagent is added? If the solution is Fe+3(aq) what will
happen when the reagent is added? KSCN
If it is Ni2+, the green solution will stay the same after adding the KSCN.
If it is Fe3+, the blood red solution will form after adding the KSCN.
,the liquid that was carefully poured into a new container decantate
To carfully pour a liquid into another conatiner decant
name the chemical: K2CrO4 potassium chromate
You have two test tubes. One test tube contains Ag+(aq) solution and the other test tube
contains Bi+3(aq). Predict what will happen when HCl(aq) is added to both test tubes. If a
reaction occurs, what is the new chemical formula? Ag+ will form a white precipitate, AgCl.
Bi3+ will remain unchanged.
You have two test tubes. One test tube contains Pb+2(aq) solution and the other test tube
contains Bi+3(aq). Predict what will happen when HCl(aq) is added to both test tubes. If a
reaction occurs, what is the new chemical formula? Pb+2(aq) will form a white precipitate,
PbCl2(s). Bi+3(aq) will remain unchanged.
You have two test tubes. One test tube contains Pb+2(aq) solution and the other test tube
contains Cu+2(aq). Predict what will happen when HCl(aq) is added to both test tubes. If a
reaction occurs, what is the new chemical formula? Pb+2(aq) will form a white precipitate,
PbCl2(s). Cu+2(aq) will remain unchanged.
Which of the chemicals are oxidants? K2CrO4
The liquid above the solid in a mixture of solid and solution supernate
A solid compound that forms as a result of mixing reagents together in a solution precipitate
, A unique chemical used in this experiment is K4Fe(CN)6(aq). What is its name? potassium
ferrocyanide
NH3(aq) and NH4OH(aq) are different ways of writing the chemical formula of the which
chemical? aqueous ammonia
Select the steps that will compose a rationale for the cation Ni+2 being absent in an unknown.
A red-pink solid did not form after the addition of H2DMG in step 3-F.
Select the step(s) that will compose a rationale for the cation Ni+2 being present in an unknown
A precipitate formed when 6 M NaOH was added to the unknown solution in step 3-A
The precipitate from step 3-A dissolved in 6 M HNO3.
A strawberry red precipitate formed in step 3-F
Separation can be achieved when a reaction occurs in a mixture. The resulting mixture will have
one chemical species in a solution and the other chemical species as a solid. The mixture is
centrifuged and the supernate is decanted into a separate test tube. Now the solid and solution
are separated from each other.
What reagent could you add to a mixture of Ag+ and Cu+2 to separate the two species? HCl
Separation can be achieved when a reaction occurs in a mixture. The resulting mixture will have
one chemical species in a solution and the other chemical species as a solid. The mixture is
centrifuged and the supernate is decanted into a separate test tube. Now the solid and solution
are separated from each other.
What reagent could you add to a mixture of Pb+2 and Bi+3 to separate the two species? HCl
Separation can be achieved when a reaction occurs in a mixture. The resulting mixture will have
one chemical species in a solution and the other chemical species as a solid. The mixture is
centrifuged and the supernate is decanted into a separate test tube. Now the solid and solution
are separated from each other. What reagent could you add to a mixture of Cu+2 and Bi+3 to
separate the two species? NH3
