1 Copper(II) ions form an aqueous complex ion, X, with chloride ions.
Which statement about X is true?
A. X has optical isomers
B. X has a square planar shape
C. X has the formula CuCl42+
D. X has a yellow colour
Your answer
[1]
2 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]
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, 3 * Transition metal complexes often have different shapes and may form a number of stereoisomers.
Describe the different shapes and the different types of stereoisomerism found in transition metal chemistry.
Use suitable examples and diagrams in your answer.
[6]
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, 4(a) A and B are compounds of two different transition elements.
Two students carry out test-tube tests on aqueous solutions of A and B.
They then analyse the results to identity A and B.
The observations of Student 1's tests are shown below.
Test A(aq) B(aq)
1 NH3(aq) added dropwise green precipitate C pale-brown precipitate E
Excess NH3(aq) added violet solution D no further change
2 HNO3(aq) no change no change
followed by Ba(NO3)2(aq) white precipitate F no change
3 HNO3(aq) no change no change
followed by AgNO3(aq) no change yellow precipitate, G
i. Analyse the results and answer the following.
Identify A and B and write their formulae.
Construct ionic equations for the formation of the products C–G from the relevant ions present in A(aq) and
B(aq).
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, [7]
ii. What was the purpose of adding HNO3(aq) first in Test 2 and Test 3?
[1]
iii. Student 2 accidentally used HCl(aq) instead of HNO3(aq) for both Test 2 and Test 3.
What different observations would Student 2 obtain?
Explain your reasoning.
[3]
iv. How could the procedure be modified to be more certain of the conclusions from Test 3?
[1]
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Which statement about X is true?
A. X has optical isomers
B. X has a square planar shape
C. X has the formula CuCl42+
D. X has a yellow colour
Your answer
[1]
2 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]
© OCR 2025. You may photocopy this page. 1 of 89 Created in ExamBuilder
, 3 * Transition metal complexes often have different shapes and may form a number of stereoisomers.
Describe the different shapes and the different types of stereoisomerism found in transition metal chemistry.
Use suitable examples and diagrams in your answer.
[6]
© OCR 2025. You may photocopy this page. 2 of 89 Created in ExamBuilder
, 4(a) A and B are compounds of two different transition elements.
Two students carry out test-tube tests on aqueous solutions of A and B.
They then analyse the results to identity A and B.
The observations of Student 1's tests are shown below.
Test A(aq) B(aq)
1 NH3(aq) added dropwise green precipitate C pale-brown precipitate E
Excess NH3(aq) added violet solution D no further change
2 HNO3(aq) no change no change
followed by Ba(NO3)2(aq) white precipitate F no change
3 HNO3(aq) no change no change
followed by AgNO3(aq) no change yellow precipitate, G
i. Analyse the results and answer the following.
Identify A and B and write their formulae.
Construct ionic equations for the formation of the products C–G from the relevant ions present in A(aq) and
B(aq).
© OCR 2025. You may photocopy this page. 3 of 89 Created in ExamBuilder
, [7]
ii. What was the purpose of adding HNO3(aq) first in Test 2 and Test 3?
[1]
iii. Student 2 accidentally used HCl(aq) instead of HNO3(aq) for both Test 2 and Test 3.
What different observations would Student 2 obtain?
Explain your reasoning.
[3]
iv. How could the procedure be modified to be more certain of the conclusions from Test 3?
[1]
© OCR 2025. You may photocopy this page. 4 of 89 Created in ExamBuilder
