Trends In Properties[]
Displacement Reactions[]
| Sodium/Potassium | Cl-(aq) | Br-(aq) | I-(aq) |
|---|---|---|---|
| Cl2(aq) | Pale Green Solution
(no reaction) |
Yellow Solution
(no reaction) |
Brown Solution
(no reaction) |
| Br2(aq) | Yellow Solution
Cl has displaced Br |
Yellow Solution
(no reaction) |
Brown Solution
(no reaction) |
| I2(aq) | Brown Solution
Cl has displaced I |
Brown Solution
Br has displaced I |
Brown Solution
(no reaction) |
Uses of Chlorine and Chlorate(l)[]
Disproportionation: The halogen is reduced and oxidised at the same time.
Chlorine with Water:[]
Cl2(aq) + H2O(l) ⇌ HClO(aq) + HCl(aq)
In Sunlight:[]
2Cl2 + 2H2O → 4HCl + O2
Chlorination of Pools[]
NaClO(s) + H2O(l) ⇌ Na+ + OH- + HClO(aq)
Reaction of Chlorine with cold, dilute NaOH solution[]
Cl2(aq) + 2NaOH(aq) → NaCl(aq) + NaClO(aq) +H2O(l)
The mixture of NaCl and NaClO is used as bleach to disinfect/kill bacteria.
The benefits to health of water treatment by chlorine outweigh its toxic effects.