Production of halogens

Describe how halogens can be extracted.

From the electrolysis of concentrated halide solutions.

Explain the process of chlorine production

Chlorine is produced industrially by the electrolysis of brine

Define brine and its components.

Brine is a solution of water with high concentrations of salts, mainly sodium chloride and some bromides and iodides, occurring naturally in salt lakes and sea water, or can be made by dissolving rock salts in water

What is produced at each electrode in the electrolysis of brine

At the cathode, hydrogen is produced, while at the anode chlorine is produced

What is left behind in the electrolysis of brine

sodium ions and hydroxide ions (sodium hydroxide solution)

Describe the production of bromine and iodine.

Bromine and iodine can be produced by bubbling chlorine gas through brine.

Why does chlorine displace bromine and iodine in the production process?

Chlorine is more reactive than bromine and iodine.

What is the chemical equation for bromine production from chlorine and what happens to the bromine produced

2Br⁻(aq) + Cl₂(g) → Br₂(g) + 2Cl⁻(aq), where bromine produced is collected, condensed into a liquid, and purified.

What is the chemical equation for iodine production and what happens to the iodine produced

2I⁻(aq) + Cl₂(g) → I₂(s) + 2Cl⁻(aq), where iodine produced is collected, purified, and condensed into a grey solid.