A student is given three unlabelled bottles, A, B and C. One contains chlorine water, one contains bromine water and one contains iodine solution. On a spotting tile, she adds a few drops of each solution to separate drops of sodium bromide solution and sodium iodide solution.
The table shows her results.
| Bottle | Added to sodium bromide solution | Added to sodium iodide solution |
|---|---|---|
| A | no change | turns brown |
| B | no change | no change |
| C | turns orange | turns brown |
Use the results to identify the halogen solution in each bottle.
Write the word equation for the reaction between bromine water and sodium iodide solution.
A chlorine atom has the electronic configuration 2.8.7. State the number of electrons a chlorine atom gains when it forms a chloride ion.
Explain why chlorine is more reactive than bromine. Use ideas about electrons in your answer.
The student predicts that fluorine would react with sodium chloride solution. Give a reason why her prediction is correct.
41 exam-style questions on Edexcel GCSE Chemistry 7.2 Group 7, covering 7.2.1 Physical properties of the halogens, 7.2.2 Reactions of the halogens, 7.2.3 Relative reactivity and displacement reactions of the halogens, and 7.2.4 Halogen displacement as a redox reaction. Each one has a worked solution and a mark scheme showing where the marks go.