Chemistry
State the observations at the anode & at the cathode during the electrolysis of –
(i) Fused lead bromide using graphite electrodes.
(ii) Copper sulphate solution using copper electrodes.
Answer
(i) The observations at the anode & at the cathode are:
At cathode — silvery grey deposit of lead metal.
At anode — reddish brown fumes of bromine vapours.
(ii) The observations at the anode & at the cathode are:
At cathode — Brownish pink copper metal is deposited at cathode during electrolysis of copper sulphate.
At anode — Copper ions are formed. Copper anode diminishes in mass.
Blue colour of CuSO4 remains unchanged.
Related Questions
Select the ion in each case, that would get selectively discharged from the aqueous mixture of the ions listed below:
(i) SO42-, NO3- and OH- ;
(ii) Pb2+, Ag+ and Cu2+.
Identify the substance underlined, in each of the following —
(i) The electrolyte used for electroplating an article with silver.
(ii) The particles present in a liquid such as kerosene, that is a non-electrolyte.
Give reasons why:
(i) Sodium Chloride will conduct electricity only in fused or aq. soln. state.
(ii) In the electroplating of an article with silver, the electrolyte sodium argentocyanide soln. is preferred over silver nitrate solution.
(iii) Although copper is a good conductor of electricity, it is a non-electrolyte.
Choose the correct answer from the options given : The electrolysis of acidified water is an example of :
- Reduction
- Oxidation
- Redox reaction
- Synthesis