Three halogens, P, Q and R, are chlorine, bromine and iodine in an unknown order. A solution of each halogen is added to solutions of the potassium halides of the other two. The results are shown.
| Halogen added | Potassium halide of P | Potassium halide of Q | Potassium halide of R |
|---|---|---|---|
| P | not done | no change | no change |
| Q | colour change | not done | colour change |
| R | colour change | no change | not done |
Which identification is correct?
P is iodine and Q is chlorine
P is chlorine and Q is iodine
P is bromine and Q is chlorine
P is iodine and Q is bromine
106 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.