Why the electrolysis of concentrated aqueous sodium chloride liberates chlorine rather than oxygen?

While electrolyzing concentrated aqueous sodium chloride, why is it that chlorine is discharged but not sodium? Hydrogen and hydroxide both exceed sodium and chlorine in terms of reduction and oxidation potential respectively.

Why is bromine discharged at the anode and not oxygen gas?

At the anode Oxygen is produced (from hydroxide ions), unless halide ions (chloride, bromide or iodide ions) are present. In that case, the negatively charged halide ions lose electrons and form the corresponding halogen (chlorine, bromine or iodine).

Why chlorine gas is given off at the anode?

Chloride ions are oxidized at the anode to produce chlorine gas. Hydrogen gas and hydroxide ions are produced at the cathode. Sodium ions migrate across the diaphragm from the anode compartment to the cathode side to produce cell liquor containing 10\% to 12\% sodium hydroxide.

Is cl2 aqueous or gas?

At room temperature, chlorine is a yellow-green gas that is heavier than air and has a strong irritating odor. It can be converted to a liquid under pressure or cold temperatures.

Why does the electrolysis of an aqueous sodium chloride solution produce hydrogen gas at the cathode?

When an electric current is passed through concentrated sodium chloride solution, hydrogen gas forms at the negative electrode , chlorine gas forms at the positive electrode, and a solution of sodium hydroxide also forms. However, sodium is too reactive for this to happen so hydrogen is given off instead.

Why chlorine gas pass through water during laboratory preparation?

Chlorine gas is passed through water to remove any gaseous HCl that may be present after it is synthesized.

What does discharge mean in electrolysis?

This simply means that in electrolysis, the more reactive the metal, the least tendency for the metal ions to be preferentially discharged at the cathode. Likewise, if the cations come from a metal which is below hydrogen in the reactivity series, then the metal ions will be preferentially discharged.

What gas is produced at the anode during electrolysis?

oxygen gas
At the anode, water is oxidized to oxygen gas and hydrogen ions. At the cathode, water is reduced to hydrogen gas and hydroxide ions.

What is the gas produced at the anode during the electrolysis of dilute hydrochloric acid?

Chloride ions are oxidised by electron loss to form chlorine gas at the positive electrode.

Is Cl A gas?

Chlorine is a yellow-green gas at room temperature. Chlorine has a pungent, irritating odor similar to bleach that is detectable at low concentrations. The density of chlorine gas is approximately 2.5 times greater than air, which will cause it to initially remain near the ground in areas with little air movement.

What is the reason for overvoltage in aqueous NaCl electrolysis?

It is due to overvoltage of oxygen gas which makes chlorine gas evolved at the anode during the electrolysis of aqueous NaCl. Overvoltage is the potential difference between a half reaction`s thermodynamically determined reduction potential and the potential at which the redox event is experimentally observed. Therefore,

What happens when sodium chloride solution is electrolysed?

Electrolysis of sodium chloride solution When an electric current is passed through concentrated sodium chloride solution, hydrogen gas forms at the negative electrode, chlorine gas forms at the positive electrode, and a solution of sodium hydroxide also forms. You might have expected sodium metal to be deposited at the negative electrode.

Why don’t ions of water get preferential discharge in electrolysis?

Therefore, in any aqueous solution, the concentration of other ions will be a lot higher than that of ions of water. If we take this aqueous solution into an electrolysis process, the ions of water will never get preferential discharged, because of the way higher concentration of other ions.

What happens to the water in a chlor-alkali electrolysis process?

In “chlor-alkali” electrolytic processes it is chloride ions that get discharged at the anode, not water. See here for an introductory look.