OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 4: Qualitative analysis of ions
Practice Exam Questions and Mark Scheme
This resource includes exam questions from both Chemistry A and Chemistry B. It is not designed as a
topic test but is instead intended as a document to support the teaching and learning of Module 1 –
Development of practical skills in chemistry.
1. Three qualitative tests are carried out on a solution of an unknown compound.
Test 1: On heating with NaOH(aq), a pungent smelling gas evolves which turns red litmus paper
blue.
Test 2: On addition of AgNO3(aq), a white precipitate forms which is soluble in dilute NH3(aq).
Test 3: On addition of Na2CO3(aq), there is no visible reaction.
What is the unknown compound?
A. ammonium bromide, NH4Br
B. ammonium chloride, NH4Cl
C. hydrochloric acid, HCl
D. sodium chloride, NaCl
Your answer
[1]
2. Four pairs of solutions are mixed.
Which pair of solutions forms a white precipitate?
A NH4Cl (aq) and NaOH(aq)
B KBr(aq) and AgNO3(aq)
C FeCl 3(aq) and NH3(aq)
D Cr2(SO4)3(aq) and BaCl 2(aq)
Your answer [1]
3. Which of the following is a correct statement about the test for Fe2+ ions in solution?
A. add NaOH(aq); brown precipitate formed, soluble in NH3(aq)
B. add NaOH(aq); brown precipitate formed, insoluble in NH3(aq)
C. add NaOH(aq); green precipitate formed, soluble in NH3(aq)
D. add NaOH(aq); green precipitate formed, insoluble in NH3(aq)
Your answer
[1]
Created in ExamBuilder 1 © OCR 2020
, OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 4: Qualitative analysis of ions
Practice Exam Questions and Mark Scheme
4. Two tests are carried out on an aqueous solution of copper(II) sulfate, CuSO4(aq).
Test 1: Addition of potassium iodide solution
Test 2: Addition of barium chloride solution
Which of the following statements is / are true?
1: Test 1 produces an off-white precipitate and a brown solution.
2: Test 2 produces a white precipitate.
3: Test 1 and Test 2 are both redox reactions.
A. 1, 2 and 3
B. Only 1 and 2
C. Only 2 and 3
D. Only 1
Your answer
[1]
5. A teacher tests a solution that has been used by students in some experiments with potassium
halides to see if it can be used with a different class.
The teacher adds silver nitrate solution to the solution that the students were using. A pale yellow
precipitate is formed. The teacher adds a few drops of dilute ammonia solution to the precipitate.
Some of the precipitate appears to dissolve and the precipitate remaining has a stronger yellow
tinge. The teacher adds excess concentrated ammonia solution to the remaining precipitate. The
precipitate does not dissolve.
What is the most likely conclusion that the teacher will reach about the solution that the students
were using?
A. The solution contains chloride ions.
B. The solution contains bromide ions.
C. The solution contains chloride and bromide ions.
D. The solution contains chloride and iodide ions.
Your answer
[1]
Created in ExamBuilder 2 © OCR 2020
PAG 4: Qualitative analysis of ions
Practice Exam Questions and Mark Scheme
This resource includes exam questions from both Chemistry A and Chemistry B. It is not designed as a
topic test but is instead intended as a document to support the teaching and learning of Module 1 –
Development of practical skills in chemistry.
1. Three qualitative tests are carried out on a solution of an unknown compound.
Test 1: On heating with NaOH(aq), a pungent smelling gas evolves which turns red litmus paper
blue.
Test 2: On addition of AgNO3(aq), a white precipitate forms which is soluble in dilute NH3(aq).
Test 3: On addition of Na2CO3(aq), there is no visible reaction.
What is the unknown compound?
A. ammonium bromide, NH4Br
B. ammonium chloride, NH4Cl
C. hydrochloric acid, HCl
D. sodium chloride, NaCl
Your answer
[1]
2. Four pairs of solutions are mixed.
Which pair of solutions forms a white precipitate?
A NH4Cl (aq) and NaOH(aq)
B KBr(aq) and AgNO3(aq)
C FeCl 3(aq) and NH3(aq)
D Cr2(SO4)3(aq) and BaCl 2(aq)
Your answer [1]
3. Which of the following is a correct statement about the test for Fe2+ ions in solution?
A. add NaOH(aq); brown precipitate formed, soluble in NH3(aq)
B. add NaOH(aq); brown precipitate formed, insoluble in NH3(aq)
C. add NaOH(aq); green precipitate formed, soluble in NH3(aq)
D. add NaOH(aq); green precipitate formed, insoluble in NH3(aq)
Your answer
[1]
Created in ExamBuilder 1 © OCR 2020
, OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 4: Qualitative analysis of ions
Practice Exam Questions and Mark Scheme
4. Two tests are carried out on an aqueous solution of copper(II) sulfate, CuSO4(aq).
Test 1: Addition of potassium iodide solution
Test 2: Addition of barium chloride solution
Which of the following statements is / are true?
1: Test 1 produces an off-white precipitate and a brown solution.
2: Test 2 produces a white precipitate.
3: Test 1 and Test 2 are both redox reactions.
A. 1, 2 and 3
B. Only 1 and 2
C. Only 2 and 3
D. Only 1
Your answer
[1]
5. A teacher tests a solution that has been used by students in some experiments with potassium
halides to see if it can be used with a different class.
The teacher adds silver nitrate solution to the solution that the students were using. A pale yellow
precipitate is formed. The teacher adds a few drops of dilute ammonia solution to the precipitate.
Some of the precipitate appears to dissolve and the precipitate remaining has a stronger yellow
tinge. The teacher adds excess concentrated ammonia solution to the remaining precipitate. The
precipitate does not dissolve.
What is the most likely conclusion that the teacher will reach about the solution that the students
were using?
A. The solution contains chloride ions.
B. The solution contains bromide ions.
C. The solution contains chloride and bromide ions.
D. The solution contains chloride and iodide ions.
Your answer
[1]
Created in ExamBuilder 2 © OCR 2020
