Halogen displacement sim
Each tube holds 2.0 cm³ of 0.10 mol/dm³ potassium halide, which is colourless.
Halogen displacement · covers the GCSE, IGCSE, O-Level topic
What the sim shows
Each tube holds 2.0 cm³ of 0.10 mol/dm³ potassium halide, which is colourless. Each drop is 0.05 cm³ of chlorine water (0.05 mol/dm³), bromine water (0.02 mol/dm³) or iodine solution (0.01 mol/dm³), up to 1.0 cm³. Reactivity falls down Group 17, so a halogen displaces any halogen below it: chlorine displaces bromine and iodine, bromine displaces iodine only, and iodine displaces neither. Where it does, the halogen set free colours the solution, bromine orange and iodine brown; where it does not, the solution only keeps the colour of the halogen added. The halide ion is oxidised and the halogen added is reduced, so the more reactive halogen is the stronger oxidising agent. Colours are worked out from each halogen's concentration in the tube.
- Liquid colours are the halogens' own colours
- Tubes are numbered on the rack
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