Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Testing for chlorides (Cl^-), bromides (Br^-) and iodides (I^-)
21 practice questions
Practice questions
11–20 of 21
Question 11
3 marks · Normal
Answer and see the solution →Explain how you can distinguish between the precipitates formed when chloride, bromide or iodide ions react with silver nitrate. In your answer, refer to both the name and the colour of each precipitate.
Question 12
4 marks · Normal
Answer and see the solution →The table shows the results of silver nitrate tests on four unknown solutions after they were all acidified with dilute nitric acid.
Solution Observation with AgNO3 after acidifying P White precipitate Q Yellow precipitate R No precipitate S Cream precipitate For each solution, write the name and formula of the ion responsible for the observation. If there is no precipitate, state 'none'.
Question 13
1 mark · Normal
Answer and check →A solution is acidified with dilute nitric acid and then tested with silver nitrate. Which observation indicates the presence of bromide ions?
- A.A yellow precipitate forms.
- B.A white precipitate forms.
- C.A cream precipitate forms.
- D.No precipitate forms.
Question 14
2 marks · Normal
Answer and see the solution →State two reasons why nitric acid is used, and not hydrochloric acid, when testing for halide ions with silver nitrate.
Question 15
4 marks · Normal
Answer and see the solution →(a)[2 marks]Name the compounds formed when silver nitrate is added to solutions containing (i) chloride, (ii) bromide, and (iii) iodide ions.
(b)[2 marks]Give the colour of each compound formed in part (a).
Question 16
2 marks · Normal
Answer and see the solution →State the names and colours of the precipitates formed when silver nitrate is added to (a) a solution containing bromide ions and (b) a solution containing iodide ions, after acidification with nitric acid.
Question 17
4 marks · Normal
Answer and see the solution →(a)[3 marks]Describe the steps you would take to test a sample for iodide ions using silver nitrate. Include all reagents added and any important precautions.
(b)[1 mark]What result would indicate that iodide ions are present?
Question 18
3 marks · Normal
Answer and see the solution →A student tests three unknown solutions by first adding dilute nitric acid and then silver nitrate solution. The results are:
Observations for unknown solutions after addition of silver nitrate Solution Observation A white precipitate B cream precipitate C no visible change Question 19
2 marks · Hard
Answer and see the solution →Explain why nitric acid must be added before silver nitrate when testing a solution for halide ions. Include what could happen if this step is skipped or done in the wrong order.
Question 20
5 marks · Hard
Answer and see the solution →When silver nitrate solution is added to separate solutions of sodium chloride, sodium bromide and sodium iodide (each has first been acidified with dilute nitric acid), different precipitates form.
(a)For each solution, name the precipitate formed and state its colour.
(i)[1 mark]Sodium chloride solution:
(ii)[1 mark]Sodium bromide solution:
(iii)[1 mark]Sodium iodide solution:
(b)Give the chemical formula for the precipitate formed in each case.
(i)[1 mark]From sodium chloride:
(ii)[1 mark]From sodium iodide: