Advertisements
Advertisements
प्रश्न
How is impure copper purified by electrolysis ? Explain.
Advertisements
उत्तर
Electrolytic refining is used for the purification of copper. In this case
Cathode : Pure copper strip
Anode : Impure copper
Electrolyte : A solution of copper sulphate and dilute sulphuric acid.
When the current is passed through the electrolyte , the copper ions of the copper sulphate solution are attracted to the cathode where they gain electrons and are deposited on pure copper strips. The impure copper loses electrons and passes into solution as soluble copper ions.
At Cathode : Cu+2 + 2e- → Cu
At anode : Cu + 2e- → Cu+2
APPEARS IN
संबंधित प्रश्न
Identify the substance underlined, in the following case
The electrolyte used for electroplating an article with silver.
Out of Cu and Ag, which is more active?
An electrolytic cell is set up using two platinum electrodes and an aqueous solution of copper (II) sulphate,
(a)draw a labelled diagram of the electrolytic cell,
(b)Name the ions present in the cell,
(c)Name the ions migrating towards the anode,
(d)Name the ions migrating towards the cathode,
(e)Name the ions which will not be discharged at electrodes during electrolysis,
(f)Write the reaction at the cathode,
(g)Write the reaction at the anode,
(h)Name the spectator ion in the solution.
State the electrode reaction at the anode during electrolysis of:
Aqueous copper sulphate solution.
Give reason for the following:
For electroplating with silver, silver nitrate is not used as an electrolyte.
Give three applications of electrolysis.
List out the main applications of electrolysis.
The following question relate to the electroplating of an article with silver.
What should be the nature of the anode?
A solution of silver nitrate is a good electrolyte but is not used for electroplating an article with silver.
Mr Ramu wants electrolyte his key chain with nickel to prevent rusting. For this electroplating
(i) Name the electrolyte
(ii) Name the cathode
(iii) Name the anode
(iv) Give the reaction at the cathode
(v) Give the reaction at the anode
