Suggest a list of metals that are extracted electrolytically.
Na, Ca, Mg and Al
What will happen during the electrolysis of aqueous solution of CuSO4 by using platinum electrodes?
(a) Copper will deposit at cathode.
(b) Copper will deposit at anode.
(c) Oxygen will be released at anode.
(d) Copper will dissolve at anode.
Value of standard electrode potential for the oxidation of Cl ions is more positive than that of water, even then in the electrolysis of aqueous sodium chloride, why is Cl- oxidized at anode instead of water?
Aqueous copper sulphate solution and aqueous silver nitrate solution are electrolysed by 1 ampere current for 10 minutes in separate electrolytic cells. Will the mass of copper and silver deposited on the cathode be same or different? Explain your answer.
Consider a cell given below:
Cu |Cu2+ || Cl |Cl2, Pt
Write the reactions that occur at anode and cathode.
Calculate the potential of hydrogen electrode in contact with a solution whose pH is 10.
Predict the products of electrolysis in each of the following.
(i) An aqueous solution of AgNO3 with silver electrodes.
(ii) An aqueous solution of AgNO3 with platinum electrodes.
(iii) A dilute solution of H2S04 with platinum electrodes.
(iv) An aqueous solution of CuCl2 with platinum electrodes.
Consider the figure given below and answer the questions (i) to (vi) that follow.
(i) Redraw the diagram to show the direction of electron flow.
(ii) Is silver plate anode or cathode?
(iii)What will happen if salt bridge is removed?
(iv)When will the cell stop functioning?
(v)How will concentration of Zn+2 cell functions?
(vi)How will the concentration of Zn+2 ions and Ag+ ions be affected after the cell becomes ‘dead'?
Write the cell reaction of a lead storage battery when it is discharged. How does the density of the electrolyte change when the battery is discharged?
If a current of 0.5 ampere flows through a metallic wire for 2 hours, then how many electrons would flow through the wire?
Calculate the standard cell potentials of galvanic cell in which the following reactions take place
Assertion (A): Mercury cell does not give steady potential.
Reason (R): In the cell reaction, ions are not involved in solution.
Arrange the following metals in the order in which they displace each other from the solution of their salts: Al, Cu, Fe, Mg and Zn.
In the button cells widely used in watches and other devices the following reaction takes place:
How much electricity in terms of Faraday is required to produce .
(i) 20.0 g of Ca from molten CaCl2?
(ii) 40.0 g of Al from molten Al203?
A solution of Ni(N03)2 is electrolyzed between platinum electrodes using a current of 5 amperes for 20 minutes. What mass of Ni is deposited at the cathode?
The quantity of charge required to obtain one mole of aluminium from
Al2O3 is (a) IF (b) 6F (c) 3F (d) 2F
In the electrolysis of aqueous sodium chloride solution, which of the half-cell reaction will occur at anode?
Unlike dry cell, the mercury cell has a constant cell potential throughout its useful life. Why?
Assertion (A): Ecell should have a positive value for the cell to function. Reason (R). Ecadlode Eanode
Assertion (A): Conductivity of all electrolytes decreases on dilution.
Reason (R): On dilution number of ions per unit volume decreases.
Assertion (A): Lm for weak electrolytes shows a sharp increase when the electrolytic solution on dilution of solution.
Electrockemistrij 63
Reason (R): For weak electrolytes dissociate partially in concentrated solution. On dilution, their degree of dissociation increases hence their Am increases sharply.
Assertion (A): Electrolysis of NaCl solution gives chlorine at anode instead of 02.
Reason (R): Formation of oxygen at anode requires overvoltage.
Define conductivity and molar conductivity for the solution of an electrolyte. Discuss their variation with concentration.
Use the data given in Q. 8 and find out which of the following is the strongest oxidizing agent.
Using the data given in Q. 8, find out in which option the order of reducing power is correct.
Conductivity of an electrolytic solution depends on
(b) concentration of electrolyte
(d) distance between the electrodes
Molar conductivity of ionic solution depends on .
(a) temperature
(b) distance between electrodes
(c) concentration of electrolytes in solution
(d) surface area of electrodes
A galvanic cell has electrical potential of 1.1 V. If an opposing potential of 1.1 V is applied to this cell, what will happen to the cell reaction and current flowing through the cell?
Solutions of two electrolytes 'A' and 'B' are diluted. The Am of 'B' increases 1.5 times while that of A increases 25 times. Which of the two is a strong electrolyte? Justify your answer.
Which reference electrode is used to measure the electrode potential of other electrodes?
Assertion (A): For measuring resistance of an ionic solution an AC source is used.
Reason (R): Concentration of ionic solution will change if DC source is used.
Assertion (A): Current stops flowing when Ecell = 0.
Reason (R): Equilibrium of the cell reaction is attained.
Assertion (A): E , increases with increase in concentration of Ag+ ions.
Ag / Ag+
Reason (R): E + has a positive value.
Ag /Ag
Consider the following figure and answer the following questions.
(i) Cell ‘A' has Ecell = 2 V and cell ‘B' has Ecen = 1.1 V which of the two cells ‘A' or ‘B' will act as an electrolytic cell. Which electrode reactions will occur in this cell?
(ii) If cell ‘A' has Ecen = 0.5 V and cell ‘B' has Ecen = 1.1 V, what will be the reactions at anode and cathode?
