Chlorine gas dissolves to some extent in water and form hydrochloric acid and hypochlorous acid as products. Therefore, an acidic solution is given when products are formed. This reaction is a dangerous one because chlorine gas is a toxic gas.
Written by: Heshan Nipuna, updated:2020/05/18
Reaction between chlorine gas and water is a reversible reaction. Therefore, all dissolved chlorine gas does not react with water. Hence, unreacted chlorine will remain in the aqueous solution. After sometime, check the pH value of aqueous solution. You may see, pH value will be lower than seven. If you send lot of chlorine gas, pH value will be very low.
Solubility of chlorine depends on the temperature. Therefore, amount of given products also depend on the temperature too. At lower temperature, solubility of chlorine is great and gives higher yield.
Hydrochloric acid (HCl) is a strong acid and hypochlorous acid (HOCl) is a weak acid. Due to exist of hydrochloric acid, dissociation of hypochlorous acid is reduced. Both acids are soluble in water.
Get a partially filled container by distilled water (to have a air space). Container should be closed on top to avoid gases are leaked to outside from the container. When you send chlorine gas to the distilled water in that container, there will be several equilibriums in several phases.
Oxidation number of chlorine is changed during the reaction. Therefore, this reaction is a red reaction. Chlorine is at 0 oxidation state in chlorine gas.
Here we are going to see how other halogens will react with water.
You should extremely careful about safety of you can other when you are doing experiment with chlorine gas. If you inhale chlorine gas, it will react with water in the mucous/linings of your lungs and form hydrochloric acid. This will destroy your lung's ability to take in oxygen and will be very painful and may cause to the death too.
This reaction produces hypochlorous acid as a product. Hypochlorous acid (HOCl) is very good disinfectant. But, presence of HCl will make difficulties to separate HOCl from HCl.