7
Avoid these mistakes
Saying a halogen displaces a more reactive halide.
1
Saying a halogen displaces a more reactive halide. A halogen only displaces halides of halogens below it in the group.
2
Writing that chlorine displaces chloride. There is no reaction because it is the same halogen.
3
Mixing up the colours: bromine is orange or yellow, iodine is brown.
4
Forgetting to balance the equation, such as writing KBr + Cl2 → KCl + Br2 without the 2s.