1. Which halogen is the most reactive?

a) Fluorine
b) Chlorine
c) Bromine
d) Iodine

2. What happens in a halogen displacement reaction?

a) A less reactive halogen displaces a more reactive halogen
b) A more reactive halogen displaces a less reactive halogen
c) The halogens combine to form a new compound
d) The halogen dissolves in an organic solvent such as hexane

3. What colour is bromine water?

a) Pale green
b) Pale purple
c) Dark brown
d) Colourless

4. Why is iodine solution prepared by dissolving iodine in potassium iodide solution?

a) To make it react faster
b) To increase its solubility
c) To change its colour
d) To make it safer to handle

5. Why is fluorine rarely used in displacement reactions?

a) It is not reactive enough
b) It is too expensive
c) It does not dissolve in water
d) It reacts violently with water

6. What is a solvent?

a) A solid that dissolves in a liquid
b) A liquid that dissolves substances
c) A gas that dissolves in a liquid
d) A solution formed by dissolving a solid in a liquid

7. Cyclohexane is used in halogen displacement reactions because?

a) It dissolves in water
b) It readily reacts with all the halogens
c) It speeds up the rate of halogen displacement reactions
d) It is immiscible in water and is a good solvent for the halogens

8. When chlorine water is added to sodium iodide solution with added cyclohexane, what colour will the cyclohexane turn?

a) Red-brown
b) Pale green
c) Yellow
d) Purple/violet

9. Why does iodine dissolve in a cyclohexane layer rather than an aqueous layer?

a) Iodine is more reactive in cyclohexane
b) Iodine is more soluble in cyclohexane
c) Cyclohexane reacts with iodine
d) Water reacts with iodine

10. Which of the following equations represents a halogen displacement reaction?

a) 2NaCl + I₂ → 2NaI + Cl₂
b) 2NaBr + CI₂ → 2NaCl + Br₂
c) 2NaCl + NaBr → 2NaBr + Cl₂
d) 2NaBr + I₂ → 2NaI + Br₂

11. What colour solution does bromine form when dissolved in cyclohexane?

a) Red-Brown
b) Purple
c) Pale green
d) A pale yellow

12. When iodine solution is added to sodium chloride solution what occurs?

a) Displacement of the chloride ions
b) Formation of sodium iodide
c) No reaction
d) A yellow precipitate forms

13. In the reaction 2Br^- → Br₂ + 2e what processing is occurring?

a) Reduction
b) Oxidation
c) Neutralisation
d) Redox

14. In the reaction Cl₂ + 2e → 2Cl^-, what is chlorine acting as?

a) A reducing agent
b) A redox agent
c) A catalyst
d) An oxidising agent

15. Which of the following should be considered when handling bromine?

a) It is a toxic pale green gas
b) It is unreactive
c) It is a toxic liquid
d) It is a reactive solid