Electrolysis Archives - Page 5 Of 9

Arrange the following according to the instruction given in the bracket : Mg2+, Cu2+, Na1+, H1+ [In the order of preferential discharge at the cathode. ]

Cu2+, H1+, Mg2+, Na1+ Lower the position of the ion, greater the tendency to be liberated at the cathode (or respective electrode).

State one observation for the following : Copper sulphate solution is electrolysed using copper electrodes.

A brownish pink deposit of copper metal is seen at the cathode when copper solution is electrolyzed using copper electrodes. The blue colour of Copper Sulphate solution does not face…

Choose the correct answer from the options A, B, C, D given. An electrolyte which completely dissociates into ions is
A. Alcohol
B. Carbonic acid
C. Sucrose
D. Sodium hydroxide

Sodium hydroxide Reason Sodium hydroxide is a strong electrolyte hence, it completely dissociates into ions.

Copy and complete the following table which refers to the conversion of ions to neutral particles.
Conversion Ionic equation Oxidation/Reduction
Chloride ion to chlorine molecule
Lead [II] ion to lead

Conversion Ionic equation Oxidation/Reduction Chloride ion to chlorine molecule Cl1- - 1e- ⟶ Cl [Cl2] Cl + Cl ⟶ Cl2 Oxidation Lead [II] ion to lead Pb2+ + 2e- ⟶ Pb Reduction

Fill in the blank with the correct choice given in the bracket – Electrolysis of aqueous sodium chloride solution will form …………… at the cathode. [hydrogen gas / sodium metal]

Electrolysis of aqueous sodium chloride solution will form hydrogen gas at the cathode.

Name the gas that is produced at the anode during the electrolysis of acidified water.

Oxygen gas

Give a reason for : Conductivity of dilute hydrochloric acid is greater than that of acetic acid.

Dil. H2SO4 is a strong electrolyte and acetic acid is a weak electrolyte. Therefore, dil. H2SO4 allows large amount of electricity to flow through it and is a good conductor of electricity…

State one relevant observation : At the anode when molten lead bromide is electrolysed using graphite electrodes

At the anode, brown fumes of bromine vapours are observed.

Choose the correct answer from the options given : The electrolysis of acidified water is an example of :
1. Reduction
2. Oxidation
3. Redox reaction
4. Synthesis

3. Redox reaction Reason — Reaction at the cathode: Hydrogen ions, H+ being the only positively charged ions migrate to the cathode. Since the cathode is a reservoir of electrons, H+…

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+.

(i) OH- ion will get discharged in preference to SO42- or NO3- ions. (ii) Ag+ ions will get discharged in preference to Pb2+ or Cu2+ ions.

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