Assertion (A): In the electrolysis of acidified water, the volume of hydrogen liberated is twice the volume of oxygen formed. Reason (R): Water has hydrogen and oxygen in the ratio of 1:2 by volume. (a) (A) is true but (R) is false. (b) (A) is false but (R) is true. (c) Both (A) and (R) are true and (R) is the correct explanation of (A). (d) Both (A) and (R) are true, but (R) is not the correct explanation of (A).

With respect to the electrolysis of copper (II) sulphate solution using copper electrodes, which statement is correct? (a) Copper metal is deposited at the negative electrode. (b) Oxygen gas is produced at the positive electrode. (c) The positive electrode increases in mass. (d) The negative electrode decreases in mass.

Which of the following reactions takes place at the anode during the electroplating of an article with silver? (a) Ag − 1e− ⟶ Ag1+ (b) Ag + 1e− ⟶ Ag1− (c) Ag − 1e− ⟶ Ag (d) None of the above

K, L and M are beakers containing three different solutions as shown below. Name the beaker which: (a) contains only ions. (b) contains only molecules. (c) has pH less than 7.

The diagram given below shows the electroplating of a spoon with silver. With reference to the diagram, answer the following questions: (a) Write an equation for the reaction that occurs at the cathode. (b) Silver nitrate solution is not preferred as an electrolyte in the above process. Give a reason. (c) Why is alternating current not used in the process? (d) What is the observation at the anode?

Differentiate between the following pairs based on the criteria given in the bracket: (a) Acetic acid and Sulphuric acid (number of replaceable hydrogen ion per molecule) (b) Electrolyte and Metallic conductor (the particles conducting electricity)

Complete the following sentences by choosing the correct option from the brackets: (a) The oxide that dissolves in caustic potash (KOH) is ............... . [ZnO / CuO] (b) The reaction that takes place at the anode during the electrolysis of molten lead bromide is ............... . [2Br − 2e− ⟶ 2Br− / 2Br− − 2e− ⟶ Br2] (c) The volume occupied by 8 grams of oxygen gas at STP is ............... litres. [5.6 / 8.96] [Atomic weight of O = 16] (d) ............... does not give hydrogen gas when it reacts with cold and very dilute nitric acid. [Cu / Mn] (e) ............... is a polar covalent compound. [HCl / CCl4]

Match Column A with Column B: Column A Column B (a) CuO + C ⟶ Cu + CO 1. Oxidation (b) Al3+ + 3e− ⟶ Al 2. Ionisation (c) PbBr2 ⟶ Pb2+ + 2Br1− 3. Reduction (d) 2O2− − 2e− ⟶ O2 4. Redox (e) HCl ⟶ H+ + Cl1− 5. Electrolytic dissociation

Aqueous copper (II) sulphate is electrolysed using copper electrodes. Which statement about the electrolysis is not correct? (a) An oxidation reaction occurs at the positive electrode. (b) The current is carried through the electrolyte by ions. (c) The positive electrode loses mass. (d) The number of copper (II) ions in the electrolyte decreases.

State the terms for the following: (a) The group obtained by removing one hydrogen atom from the parent alkane. (b) Two metal plates or wires through which the current enters and leaves the electrolytic cell. (c) The amount of substance which contains the same number of units as the number of atoms in carbon-12. (d) The tendency of an atom to pull a shared pair of electrons towards itself in a compound. (e) The formula which represents the simplest ratio between the atoms of elements present in a compound.

Arrange the following according to the instructions given in brackets: (a) C2H2, C3H6, CH4, C2H4 (In the increasing order of the molecular weight) (b) Cu2+, Na+, Zn2+, Ag+ (The order of Preferential discharge at the cathode)

Answer the following with reference to the electrolytic refining of copper: (a) What is used as the anode? (b) Where is pure copper deposited? (c) Write the cathode reaction.