Electro Chemistry Questions for CBSE Class 12th

In which of the following cells E cell = E cell ∘ ?

Which of the following statement is correct?

The reaction which occur in the Galvanic cell is MnO 4 − + 8 H + + 5 Fe 2 + ⟶ Mn 2 + + 5 Fe 3 + + 4 H 2 O E ∘ MnO 4 − , Mn 2 + , H + ∣ Pt = 1 .51 V and E ∘ Fe 3 + , Fe 2 + ∣ Pt = 0 .77 V (Q). The other concentrations are kept at unity except reducing Mn 2 + to 0.50 M, the emf of the cell is increased by

Find out which of the following is the strongest oxidising agent?

E cell o for some half-cell reactions are given below. (i) H + ( aq ) + e − ⟶ 1 2 H 2 ( g ) ; E cell ∘ = 0 .00 V (ii) 2 H 2 O ( l ) ⟶ O 2 ( g ) + 4 H + ( aq ) + 4 e − ; E cell ∘ = 1 .23 V (iii) 2 SO 4 2 − ( aq ) ⟶ S 2 O 8 2 − ( aq ) + 2 e − ; E cell ∘ = 1 .96 V On the basis of these mark the correct answer.

Name the cell given in the figure.

Molar conductivity of ionic solution depends on …….

The electrochemical cell shown below is a concentration cell. M / M 2 + (saturated solution of a sparingly soluble salt MX 2 ∥ M 2 + 0 .00001 mol dm − 3 / M The emf of the cell depends on the difference in concentration of M 2+ ions at the two electrodes. The emf of the cell at 298 is 0.059 V. The value of ΔG kJ mol − 1 for the given cell is (take 1 F = 96500 C mol − 1 )

Electrolysis of aq. K 2 SO 4 using inert electrodes is carried out by passing 9650 coulombs. Weight of the substance obtained at cathode is

Consider the half-cell reduction reaction Mn 2 + + 2 e – Mn , E ° = – 1 . 18 V Mn 2 + Mn 3 + + e – , E ° = – 1 . 51 V The E ° for the reaction 3 Mn 2 + Mn 0 + 2 Mn 3 + , and possibility of the forward reaction are respectively

How many gram of cobalt metal will be deposited when a solution of cobalt(II) chloride is electrolyzed with a current of 10 amperes for 109 minutes (1 Faraday=96,500 C Atomic mass of Co=59 u)

Identify the reaction from following having top position in EMF series (Std. red. potential) according to their electrode potential at 298 K.

Which one of the following is a semiconductor

Which of the following is best conductor of electricity?

The conductivity of a saturated solution of B a S O 4 is 3 . 06 × 10 – 6 ohm – 1 cm – 1 and its equivalent conductance is 1 . 53 ohm – 1 cm – 1 equivalent – 1 . The K sp of the BaSO 4 will be

Cost of electricity to deposit 108 grams of Aluminium is ‘X’. Cost of electricity to deposit 48 grams of Magnesium would be

In the given reaction, 2 Cu + ( aq ) ⇌ Cu 2 + ( aq ) + Cu ( s ) E Cu + / Cu ∘ = 0 .6 V and E Cu 2 + / Cu ∘ = 0 .41 V Find out the equilibrium constant.

Which of the following statement is true for molar conductivity?

The resistance of the cell containing KCI solution at 23 o C was found to be 55 Ω . Its cell constant is 0.616 cm-l. The conductivity of KCI solution Ω − 1 cm − 1 is.

The Gibbs energy for the decomposition of Al 2 O 3 at 500 o C is as follows 2 3 Al 2 O 3 ⟶ 4 3 Al + O 2 ; Δ r G = + 960 kJ mol − 1 The potential difference needed for the electrolytic reduction of aluminium oxide (Al 2 O 2 ) at 500 o C is atleast

Which of the following equation(s) is/are incorrect?

Select the correct statement(s) for the weak electrolyte.

Consider the following statements about the application of electro chemical series. I. Comparison of relative oxidising and reducing powers of substances. Il. Prediction of evolution of hydrogen during reaction of a metal with acid. III. Prediction of spontaneity of a redox reaction. IV. Calculation of amount of metal deposited at cathode. The true statement(s) is/are

Match Column I with Column II related to the figure given below and then select the appropriate option from the codes given below. Column I Column II A. Figure represents 1. Reduction B. O 2 ( g ) + 4 H + ( aq ) + 4 e − ⟶ 2 H 2 O ( l ) 2. Corrosion of iron of atmosphere C. Fe ( s ) ⟶ Fe 2 + ( aq ) + 2 e − 3. Oxidation D. 2 Fe 2 + ( aq ) + 2 H 2 O ( l ) + 1 2 O 2 ⟶ Fe 2 O 3 + 4 H + ( aq )

The incorrect statement about lead storage battery is

Statement 1 : The electrode may be negatively charged or positively charged, with respect to solution. Statement 2 : Metal atom of electrode has tendency to go into solution as ion and leave behind the electron at the electrode.

Statement 1 : DC can not be used during measurement of resistance of an ionic solution. Statement 2 : DC changes the composition of solution and solution cannot be connected to the bridge like metallic wire.

Match the following Column I with units given in Column II and choose the correct option from the codes given below. Column I Column II A. Resistivity 1. ohm – 1 B. Conductance 2. ohm m C. Conductivity 3. S cm – 1

I. Metallic electrodes are dipped into electrolyte. II. Half-cells are connected by metallic wire through voltmeter and switch. III.There is no need of salt bridge if the electrodes are dip in the same electrolyte. Which of the following statements is/are true for the above diagram? Choose the correct option.

What will happen to pH of brine solution if electrolysed?

Calculate the time required to deposite 2 x 10 -3 cm thick layer of silver (density 1.05 g cm -3 ) on the surface of area 1 00 cm -3 by passing a current of 10 A through silver nitrate solution?

The true statement about mercury cell is

Flow of electron is from

An electrochemical cell can behave like an electrolytic cell when ………

A 4.0 M aqueous solution of NaCl is prepared and 500 mL of this solution is electrolysed. This leads to evolution of chlorine gas at one of the electrodes. (Q) Calculate the number of moles of chlorine gas evolved during the electrolysis.

While charging the lead storage battery.

Two Faraday of electricity is passed through a solution of CuSO 4 . The mass of copper deposited at the cathode is (atomic mass of Cu = 63.5 u)

Molar conductance of 2 M strong electrolyte AB is ‘ X ‘ mho cm 2 mole – 1 . Specific conductivity of the solution at the same temperature is 0.09 mho cm -1 . Value of ‘X’ is

An aqueous solution of Na 2 SO 4 in water is electrolysed using Pt electrodes. The products at the cathode and anode are respectively :

Cadmium amalgam is prepared by electrolysis of a solution of CdCl 2 , using a mercury cathode. How long should a current of 4 A be passed in order to prepare 10% by wt. Cd in Cd-Hg amalgam on cathode of 4.5 g Hg? (atomic wt. of Cd : 112)

At equilibrium :

Pure water does not conduct electricity because it :

A conductance cell was filled with a 0.02 M KCI solution which has a specific conductance of 2.768 x 10 -3 ohm -1 cm -1 .If its resistance is 82.4 ohm at 25 o C, the cell constant is:

what is the equivalent conductivity (S cm 2 eq -1 ; of 0.001M H 2 SO 4 (aq.) solution at 298 K? 1f measured conductivity of H 2 SO 4 (aq.) solution was found to be 8 x10 -4 ohm -1 cm -1 .

Which of the following is arranged in increasing order of ionic mobility ?

When 0.1 mol M n O 4 2 – is oxidised, the quantity of electricity required to completely oxidise M n O 4 2 – to M n O 4 1 – is

The weight of silver (at. wt. = 108 ) displaced by a quantity of electricity which displaces 5600 mL of O 2 at STP will be

In the electrochemical cell : Zn ZnSO 4 ( 0 .01 M ) ∥ CuSO 4 ( 1 .0 M ) Cu the emf of this Daniel cell is E 1 . When the concentration of ZnSO 4 is changed to 1.0 M and that of CuSO 4 changed to 0.01 M,the emf changes to E 2 . From the following, which one is the relationship between E 1 and E 2 (Given, RT/F = 0.059)

Two amperes of current is passed through acidulated water for ‘t’ seconds to decompose 18 grams of water . Value of ‘t’ is equal to

Reduction potential of Hydrogen electrode is minimum when it is in contact with

Number of electrons required to deposit 56 grams of Iron from molten FeCl 3 will be

Given, Λ m o   H 2 SO 4 =    x   Scm 2    mole − 1 ; Λ m o   K 2 SO 4 =    y   Scm 2    mole − 1 ;     Λ m o   CH 3 COOK =    z   Scm 2    mole − 1 Λ m o   CH 3 COOH will be Scm 2    mole − 1

Which one of the following aqueous solution when subjected to electrolysis using inert electrodes shows change in concentration without any change in composition.

Equivalent conductance of Ba + 2     and    Cl − ions at infinite dilution are 127 mho cm 2 geq – 1 and 76 mho cm 2 geq – 1 respectively. Equivalent conductance of BaCl 2 at infinite dilution is mho cm 2 geq – 1 .

Molar conductance of decimolar electrolyte is ‘ X ‘    mhocm 2 mole − 1 . Specific conductance would be mhocm – 1

X and Y respectively

Statement–I: 0.1 M HCl is a better conductor than 0.1 M NaCl Statement-II: Molar conductance of CH 3 COOH increases with increase in dilution.

Cost of Electricity to deposit one gram of Hydrogen is Rs 200. Cost of Electricity to deposit six grams of Magnesium will be

2F of electricity can decompose ————— moles of acidulated water

Which of the following is a strong electrolyte ?

The S.R.Ps of Cu 2+ /Cu, Hg 2+ / Hg and Zn 2+ /Zn are respectively 0.34V, 0.85 V and – 0.76 V. The wrong statement is

The E M + 3 | M + 2 0 values for Cr, Mn, Fe and Co are – 0.41, + 1.57V, + 0.77 and + 1.97V respectively. For wihch one of these metals the change in oxidation sate from + 2 to + 3 is easiest?

Based on the data given below, the correct order of reducing power is :

The reference electrode is made by using

The following cell is found to have EMF equal to zero. Pt, H 2 (x atm) | 0.01MH + || 0.1MH + | H 2 (y atm), Pt . The ratio x y is

The relationship between free energy and electrode potential is

The EMF of a cell formed by combining a particular electrode with standard calomel electrode is found to be 0.344 V and calomel electrode is found to act as cathode. If the same electrode is combined with standard hydrogen electrode, the EMF of the cell will be (Given standard reduction potential, E 0 Calomel = + 0 . 244 V )

Given E Cr + 3 / Cr 0 = – 0 . 72 V ; E Fe 2 + / F e 0 = – 0 . 42 V The potential for the cell, Cr|Cr 3+ (0.1M||Fe 2+ (0.01M| Fe is

The potential of hydrogen electrode is –118 mV. The H + concentration of the solution is

The number of coulombs required to deposit 5.4 g. of Aluminium when the given electrode reaction is represented as Al 3 + + 3 e – Al

Consider the following four electrodes: A = Cu 2+ (0.0001 M)/Cu (s) B = Cu 2+ (0.1 M)/Cu (s) C = Cu 2+ (0.01 M)/Cu (s) D = Cu 2+ (0.001 M)/Cu (s) If the standard reduction potential of Cu is + 0.34V, the reduction potentials (in volts) of the above electrodes follow the order

One coulomb of charge passes through solutions of AgNO 3 and CuSO 4 . The ratio of the amounts of silver and copper deposited on platinum electrodes used for electrolysis is

Electric charge on 1gm ion of N 3– is

One Faraday of electricity is passed separately through one litre of one molar aqueous solutions of (i) AgNO 3 (ii) SnCl 4 and (iii) CuSO 4 . The number of moles of Ag, Sn and Cu deposited at cathode are respectively

When an electric current is passed through acidulated water, 112 ml of hydrogen gas at NTP is collected at the cathode in 965 seconds. The current passed in amperes is

During the electorlysis of cryolite, aluminium and fluorine are formed in ….. molar ratio

Time required to deposit one millimole of aluminium metal by the passage of 9.65 amperes through aqueous solution of aluminium ions is

The conductivity of 0.001 M acetic acid is 5 × 10 –5 S cm –1 and is 390.5 S cm 2 mol –1 then the calculated value of dissociation constant of acetic acid would be

The limiting molar conductivities λ o for NaCl, KBr an KCl are 126, 152 and 150 S. cm 2 mol –1 respectively. Then λ o for NaBr is

965 amp current is passed through molten metal chloride for one minute and 40 seconds during electrolysis. The mass of metal deposited is 9 gm at the cathode. The valency of metal atom (at.wt = 27) is

Molar conductivity of a solution is 1.26 × 10 2 Ω – 1 cm 2 mol –1 . Its molarity is 0.01M. Its specific conductivity will be

What is the approximate quantity of electricity in coulombs required to deposit all the silver from 500 ml 1M AgNO 3 aqueous solution ? (At. wt. of Ag = 108)

The specific conductance of 0.1N KCl solution at 23 0 C is 0.012 ohm –1 cm –1 . The resistance of cell containing the solution at the same temperature was found to be 55 ohm. The cell constant will be

At 25 0 C, the ionic mobility of CH 3 COO – , H + are respectively 4.1 × 10 -4 , 3.63 × 10 -3 cm /sec. The conductivity of 0.001M CH 3 COOH is 5 × 10 -5 S.cm -1 . Dissociation constant of CH 3 COOH is

Equivalent conductance ( λ ) vs concentration graphs are given for some electrolytes X, Y and Z. Here X, Y and Z are respectively

The resistance of 0.05M KCl solution at 25 0 C is 100 ohm in a cell whose cell constant is 0.3765cm –1 . The specific conductivity of KCl solution is

The EMF of the following cells are Cu|Cu 2+ (1M) || Ag + (1M) | Ag, E o = 0.46 V Zn | Zn 2+ (1M) || Cu 2+ (1M) | Cu, E o = 1.10V The EMF of the cell Zn|Zn 2+ (1M)|| Ag + (1M) | Ag will be

For the following cell Zn / Zn 2+ // Cd 2+ / Cd E cell = 0.30V and E 0 cell = 0.36V. Then the value of [Cd 2+ ] / [Zn 2+ ] is

The standard electrode potential of the two half cells are given below Ni + 2 + 2 e – Ni ; E 0 = – 0 . 25 Volt Zn + 2 + 2 e – Zn ; E 0 = – 0 . 77 volt The voltage of cell formed by combining the two half cells would be

A cell constructed by coupling a standard copper electrode and a standard magnesium electrode has emf of 2.7 volts. If the standard reduction potential of copper electrode is + 0.34 volt, that of magnesium electrode is

In the electrochemical conversion (Kolbe’s eletrolysis) of R–COONa to R–R, 1A current was passed for 965 seconds. Calculate the amount of R–R formed in this process (Faraday constant = 96,500 C mol –1 )

Aluminium displaces hydrogen from dilute HCl whereas silver does not. The e.m.f. of a cell prepared by combining Al/Al 3+ and Ag/Ag + is 2.46 V. The reduction potential of silver electrode is + 0.80 V. The reduction potential of aluminium electrode is

The solution of nickel sulphate in which nickel rod is dipped is diluted 10 times. The potential of nickel

The standard reduction potentials for the two half-cell reactions are given below : The standard free energy change for the reaction is given by

The standard EMF for the cell reaction, Zn + Cu 2 + Cu + Zn 2 + is 1.1 volt at 25 0 C. The EMF for the cell reaction, when 0.1 M Cu 2+ and 0.1 M Zn 2+ solutions are used, at 25 0 C is

E 0 for F 2 + 2 e – 2 F – is 2.8 E 0 for 1 2 F 2 + e – F – is

E 0 for the reaction Fe + Zn 2 + Zn + Fe 2 + is – 0.35 V. The given cell reaction is

The standard potentials (E 0 ) for the half reactions are as the emf for the cell reaction is

Deduce from the following E° values of half cells, what combination of two half cells would result in a cell with the largest potential? I) A A + + e ; E° = –0.24V II) B – B + e ; E° = –2.1V III) C C 2 + + 2 e ; E° = –0.38V IV) D 2 – D – + e ; E° = –0.59V

The half cell reactions for the corrosion are, 2 H + + 1 2 O 2 + 2 e – H 2 O ; E 0 = 1.23V Fe 2 + + 2 e – Fe ( s ) ; E 0 = – 0.44V. Find the ΔG 0 (in kJ) for the overall reaction

The standard reduction potentials of Ag, Cu, Co and Zn are 0.799, 0.337, –0.277 and – 0.762V respectively. Which of the folloing cells will have maximum cell e.m.f.?

E o of Fe|Fe 2+ is +0.44V, E o of Cu|Cu 2+ is –0.32V. Then in the cell

The standard reduction potentials of Zn 2+ | Zn, Cu 2+ |Cu and Ag + |Ag are respectively – 0.76, 0.34 and 0.8V. The following cells were constructed a) Zn / Zn 2+ // Cu 2+ / Cu b) Zn / Zn 2+ // Ag + / Ag c) Cu / Cu 2+ // Ag + / Ag What is the correct order of E 0 cell of these cells ?

The standard Potentials at 25 0 C for the half reactions are given against them below: Zn 2 + + 2 e – Zn ; E 0 = – 0 . 762 V Mg 2 + + 2 e – Mg ; E 0 = – 2 . 37 V When Zn dust is added to a solution of MgCl 2

The standard reduction potential at 298K for the following half cell reaction Which of the following is strongest reducing agent?

Statement I : Rusting of iron can be prevented by coating the Iron article with zinc. Statement II : SRP of Zn +2 /Zn is more negative than SRP of Fe +2 /Fe

Statement I : Molar conductance increases with increase in dilution for strong electrolyte Statement II : As dilution increases, inter ionic attractions decreases in strong electrolytes

Statement I : Electrolysis of Brine solution using inert electrodes liberates H 2 at cathode Statement II : SRP of value of NHE is greater than SRP value of Na + /Na

Statement I : Rusting of iron increases with decrease in pH. Statement II : Reduction of O 2 is favoured at lower P H

Statement I : Life span of Daniel cell can be increased by increasing the size of zinc electrode Statement II : Emf of a galvanic cell varies with concentration of electrolyte

Statement I : Under standard conditions, Emf of Li-F 2 couple is maximum Statement II : SRP value of Li + /Li is most negative and SRP of Pt,F 2 /F – is most positive

Statement I : During electrolysis of aqueous CuSO 4 using Pt electrodes, p H progressively decreases Statement II : Electrolysis of aqueous CuSO 4 using Pt electrodes, the solution becomes acidic due to the formation of H 2 SO 4

An electric current is passed through silver nitrate solution using silver elecrodes. 10.79 g of silver was found to be deposited on the cathode. If the same amount of electricity is passed through copper sulphate solution using copper electrodes, the weight of copper deposited on the cathode is

The equilibrium constant for the reaction : : E 0 = 0.46 V at 298 K is

Standard electrode potential of three metals X, Y and Z are –1.2 V, +0.5 V and –3.0 V respectively. The reducing power of these metals will be

Al 2 O 3 is reduced by electrolysis at low potentials and high currents. If 4.0 × 10 4 amperes of current is passed through molten Al 2 O 3 for 6 hours. What mass of aluminium is produced ? (Assume 100% current efficiency. At mass of Al = 27g mol –1 )

For the cell reaction at 298 K. The standard Gibbs energy of the cell reaction is [Given that Faraday constant F = 96500Cmol –1 ]

A button cell used in watches functions as If half cell potentials are The cell potential will be

Kohlrausch’s law is applicable

The Gibbs energy for the decomposition of Al 2 O 3 at 500 0 C is as follows The voltage needed for the electrolytic reduction of aluminium oxide (Al 2 O 3 ) at 500 0 C is at least

Which of the following is the strongest oxidising agent ?

The arrangement of metals from more reactive to less reactive gives us a series known as

Aqueous solution of copper sulphate is subjected to electrolysis using Pt electrodes. False statement about this process is

Molar conductance of an electrolyte A 3 B 2 is ‘X’ mho cm 2 mole -1 . Equivalent conductance of A 3 B 2 will be . . . mho cm 2 geq -1

Aqueous solution of ‘X’ is electrolyzed using inert electrodes. Hydrogen is liberated at cathode and oxygen is liberated at anode. ‘X’ is

Aqueous solution of CuSO 4 is subjected to electrolysis using copper electrodes. Correct statement about the process is

For the generation of electrical potential of 1.1 V, the ideal concentration of zinc and copper ion (in mol dm -3 ) in the Galvanic cell is

Select the incorrect statement

Select the correct statement(s) for the given reaction. Cu s + 2 Ag + aq Cu 2 + aq + 2 Ag s

Select the incorrect statement about standard hydrogen electrode.

Which of the following statement(s) is/are true regarding to the cell constant?

E cell o of the reaction is Zn ( s ) + Cu 2 + ( aq ) Zn 2 + aq + Cu ( s ) ; If E Zn 2 + / Zn o = – 0 . 76 , E Cu 2 + / Cu o = 0 . 34 V

What happens to the composition of metallic conductor when electron enters at one end and go out through other end?

Standard electrode potential (reduction potential) becomes equal to cell potential, when

Select the incorrect statement

In a Galvanic cell

KCI solution is generally used to determine the cell constant because

In the reaction of copper with nitric acid,

Which of the following statement is incorrect?

Which of the following information(s) is/are false for this figure?

Calculate the standard Gibbs free energy of Zn ( s ) + Cu 2 + ( aq ) ⟶ Zn 2 + ( aq ) + Cu ( s ˙ )

At 25 o C, molar conductance of 0.1 molar aqueous solution of ammonium hydroxide is 9 . 54 Ω – 1 cm 2 mol – 1 and at infinite dilution, its molar conductance is 238 ohm – 1 cm 2 mol – 1 . The degree of ionisation of ammonium hydroxide at the same concentration a4d temperature is

Resistance of 0.2 M solution of an electrolyte is 50 Ω . The specific conductance of the solution is 1.3 Sm -1 .If resistance of the 0.4 M solution of the same electrolyte is 260 Ω ,its molar conductivity is

Molar conductivities Λ m ∘ at infinite dilution of NaCl, HCI and CH 3 COONa are 126.4,425.9 and 91.0 S cm 2 mol -1 respectively. Λ m ∘ for CH 3 COOH will be

The reactions involved during rusting of iron are

Given, E Ni 2 + / Ni = 0 .25 V ∘ , E Cu 2 + / Cu = 0 .34 V ∘ E Ag + / Ag = 0 .80 V ∘ and E Zn 2 + / Zn = − 0 .76 V ∘ Which of the following reactions under standard condition will not take place in the specified direction?

Which of the following statements is/are false for the given figure?

Consider the following statements. I. Lower the value of E o , more will be the reducing power. II. If E o = -ve hydrogen gas is more stable than the reduced form of the species. III. Lithium has the lowest electrode potential. IV. Lithium ion is the weakest oxidising agent. The correct statements are

Match the following columns. Column I Column II A. Fe 3 + and I − p. E cell ∘ = + ve B. Fe 3 + and Br − q. ΔG ∘ = + ve C. Zn and H + r. E cell ∘ = − E electrode ∘ D. Br and Fe 2 + s. ΔG ∘ = − ve Given, E Fe 3 + / Fe 2 + ∘ = 0 .77 , E 1 2 I 2 / 1 − ∘ = + 0 .54 E 1 / 2 Br 2 / Br − = 1 .09 , E Zn 2 + / Zn ∘ ∘ = − 0 .76

Statement 1 : Solid NaCl does not conduct electricity. Statement 2 : Solid NaCl has no free ions.

Statement 1 :Electrical conductance through metals is called electronic conductance. Statement 2 : This is due to movement of electrons.

Statement 1 : Stainless steel undergoes rusting. Statement 2 : Chromium forms an oxide layer over the stainless steel.

Statement 1 : Copper sulphate solution is stored in zinc pot. Statement 2 :Zinc is more reactive than copper so it displaces copper from copper sulphate solution.

Which of the following reaction is preferred at anode during the electrolysis of H 2 SO 4 at higher concentration?

Statement 1 : Pure water conduct electricity. Statement 2 : It is unionised.

When aqueous sodium chloride solution is electrolysed

Galvanisation is

The incorrect statement related to batteries is

Match the following columns. Column I (Substance) Column II (Product after electrolysis) A. Aqueous solution of AgNO 3 using Ag electrodes p. Oxygen is produced at anode B. Aqueous solution of AgNO 3 using Pt electrodes q. Hydrogen is produced at cathode C. Dilute solution of H 2 SO 4 using Pt electrodes r.. Silver is deposited at cathode D. Aqueous solution of CuCl 2 using Pt electrodes s. Neither O 2 nor H 2 is produced

The reaction which occur in the Galvanic cell is MnO 4 − + 8 H + + 5 Fe 2 + ⟶ Mn 2 + + 5 Fe 3 + + 4 H 2 O E ∘ MnO 4 − , Mn 2 + , H + ∣ Pt = 1 .51 V and E ∘ Fe 3 + , Fe 2 + ∣ Pt = 0 .77 V (Q) How would the emf of the cell be increased above the standard emf ?

Find out the correct statement.

A 4.0 M aqueous solution of NaCl is prepared and 500 mL of this solution is electrolysed. This leads to evolution of chlorine gas at one of the electrodes. Find out the maximum weight of amalgam formed from the solution [if cathode is Hg].

Calculate the molar conductivity of 0.2 mol L -1 KCl solution.

NaCl aqueous solution on electrolysis gives H 2 ( g ) , Cl 2 ( g ) and NaOH . 2 Cl − ( aq ) + 2 H 2 O ⟶ 2 OH − ( aq ) + H 2 ( g ) + Cl 2 ( g ) . In 20 L of NaCl solution (20% by weight), current of 25. A with 62% of current efficiency is passed. Which of the following reaction will occur at anode?

Using the data given below find out the strongest reducing agent. E ⊖ Cr 2 O 7 2 − / Cr 3 + = 133 V ; E ⊖ Cl 2 / Cl − = 1 .36 V E ⊖ MnO 4 − / Mn 2 + = 1 .51 V ; E ⊖ Cr 3 + / Cr = − 0 .74 V

For the given cell, Mg Mg 2 + ∥ Cu 2 + Cu

Cell potential of commonly used mercury cell is

Statement 1: Mercury cell does not give steady potential. Statement 2: In the cell reaction, ions are not involved in solution.

Statement 1: E cell should have a positive value for the cell to function. Statement 2: E cathode < E anode

Statement 1: Current stops flowing when E cell = 0 . Statement 2: Equilibrium of the cell reaction is attained.

E cell o = 1 . 1 V for Daniell cell. Which of the following expressions are correct description of state of equilibrium in this cell?

Statement 1: Copper sulphate can be stored in zinc vessel. Statement 2: Zinc is less reactive than copper.

Statement 1 : Λ m for weak electrolytes shows a sharp increase, when the electrolytic solution is diluted. Statement 2 : For weak electrolytes degree of dissociation increases with dilution of solution.

Match the items of Column I and Column II on the basis of data given below. E F 2 / F − ∘ = 2 .87 V , E Li + / Li ∘ = − 3 .5 V , E Au 3 + / Au ∘ = 1 .4 V , E Br 2 / Br − ∘ = 1 .09 V Column I Column II A F 2 1. Metal is the strongest reducing agent. B Li 2. Metal ion which is the weakest oxidising agent. C Au 3+ 3. Non-metal which is the best oxidising agent. D Br – 4. Unreactive metal. E Au 5. Anion that can be oxidised by Au 3+ . F Li + 6. Anion which is the weakest reducing agent. G F – 7. Metal ion which is an oxidising agent.

Statement 1: For measuring resistance of an ionic solution, an AC source is used. Statement 2: Concentration of ionic solution will change if DC source is used.

Match the terms given in Column I with the items given in Column II. Column I Column II A. Λ m 1. Intensive property B. E cell ∘ 2. Depends on number of ions/volume C. K 3. Extensive property D. Δ r G cell 4. Increases with dilution

Given E Cr 3 + / Cr ∘ = 0 .74 V ; E MnO 4 − / Mn 2 + ∘ = 1 .51 V E Cr 2 O 7 2 − / Cr 3 + = 1 .33 V ; E Cl / Cl − ∘ = 1 .36 V Based on the data given above strongest oxidising agent will be

Which of the following reactions are feasible, if the electrode potential are E o I 2 / I – = 0 . 54 V , E o Fe 3 + / Fe 2 + = 0 . 77 V , E o Ag + / Ag = 0 . 8 V and E o Cu 2 + / Cu = 0 . 34 V

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.

If the molar conductivities at infinite dilution of NH 4 CI, NaOH and NaCl respectively are 120.8, 210.4 and 110 S cm 2 mo1 -1 . Then the limiting molar conductivity of NH 4 OH is equal to

For E o Zn 2 + / zn = – 0. 76 V the E.M.F of the cell Pt ( s ) H 2 ( g ) ( lbar ) H + ( aq ) 1 M | | Zn 2 + ( aq ) 1 ( M ) ∣ Zn will be

Electrolysis of aq. K 2 SO 4 using inert electrodes is carried out by passing 19300 coulombs. Weight of the substance obtained at anode is

Electrolysis of aq. K 2 SO 4 using inert electrodes is carried out by passing 100 amperes for 965 seconds. Volume of the substance obtained at cathode(at STP) is

Molar conductance of decimolar strong electrolyte AB is 360 mho cm 2 mole – 1 . Specific conductivity of the solution at the same temperature would be——- mho m -1

Molar conductance of 2 M strong electrolyte AB is ‘ X ‘ mho cm 2 mole – 1 . Specific conductivity of the solution at the same temperature is 0.09 mho cm -1 . Value of ‘X’ is

Cell notation of a galvanic cell is represented as Ni ( s ) / Ni + 2 ( M 1 ) / / Cl – ( M 2 ) / / 1 2 Cl 2 ( 1 atm ) , Pt ( s ) . Emf of the cell is minimum when the values of M 1 and M 2 are

Cell notation of a galvanic cell is represented as Ni ( s ) / Ni + 2 ( M 1 ) / / Cl – ( M 2 ) / / 1 2 Cl 2 ( 1 atm ) , Pt ( s ) . Emf of the cell is minimum when the values of M 1 and M 2 are

Oxidation potential of hydrogen electrode is least when it is in contact with a solution of

Oxidation potential of hydrogen electrode is maximum when it is in contact with a solution of

Oxidation potential of hydrogen electrode is minimum when it is in contact with a solution of

Electrolytes when dissolved in water dissociate into ions because :

The amount of an ion liberated on an electrode during electrolysis does not depend upon :

A highly concentrate solution of potassium sulphate in water is electrolysed using inert electrodes. The products at the cathode and anode are respectively.

The passage of current through a solution of certain electrolyte results in the evolution of H 2 (g) at cathode and Cl 2 (g) at anode. The electrolytic solution is :

Total charge required for the oxidation of two moles Mn 3 O 4 into MnO 4 2- in presence of alkaline medium is :

The electrolysis of a solution resulted in the formation of H 2 (g) at the cathode and O 2 (g) at the anode. The solution is :

In the commercial preparation of aluminum, aluminum oxide (Al 2 O 3 ) is electrolyzed at 1000 o C. How many coulombs of electricity are required to give 54 kg of aluminum? Assume following reaction takes place at cathode : Al 3 + + 3 e − ⟶ Al

Which is correct statement about the electrolysis of aqueous solution of CuSO 4 with copper cathode and Pt anode?

A salt bridge contains :

Standard electrode potential of SHE at 298 K is :

When a concentrated solution of an electrolyte is diluted?

The specific conductance of a saturated solution of silver bromide is k scm -1 . The limiting ionic conductivity of Ag + and Br – ions are x and y, respectively The solubility of silver bromide in gL -1 is : (molar mass of AgBr = 188)

Oxidation potential of Hydrogen electrode in contact with 0.05 M H 2 SO 4 solution is

Reduction potential of Iron electrode in contact with 0.01M FeSO 4 solution is E Fe + 2 / Fe o   =   − 0 .44 V

Given E Zn + 2 / Zn o   =   − 0 .76 V ;    E F e 2 + / Fe o =    − 0 .44 V ; E Sn + 2 / Sn o   =   − 0 .14 V . Identify the correct statement from the following

Calculate emf of a cell Ag(s) / Ag + (1M) / Mg + 2 (1M) / Mg(s) and also predict the spontaneity of cell reaction. E Ag + / Ag 0 =   + 0 .8 V ;    E Mg + 2 / Mg o =   − 2 .37 V

Reaction Emf Gibbs free energy H 2   +   Cl 2     2 HCl E 1 ΔG 1 1 2 H 2 + 1 2 Cl 2     HCl E 2 ΔG 2 Correct relation is

Electrolysis of aqueous Copper Sulphate is carried out using inert electrodes by passing one faraday of electricity .Volume of gas liberated at anode under STP conditions will be

A q u e o u s s o l u t i o n o f A g N O 3 i s e l e c t r o l y s e d u sin g P t e l e c t r o d e s . P r o d u c t s o b t a i n e d a t a n o d e a n d c a t h o d e r e s p e c t i v e l y

Correct decreasing order of Electrochemical equivalent values is

50% H 2 SO 4 solution is electrolyzed using inter electrodes. The product obtained at anode is

1 Faraday can deposit/liberate one gram atom of metal at cathode during the electrolysis of (inert electrodes are used)

For the cell reaction: 2 Fe ( aq ) 3 + + 2 I ( aq ) – ⟶ 2 Fe ( aq ) 2 + + I 2 ( aq ) E o cell = 0 . 24 V at 298 K . The standard Gibbs energy Δ r G ° of the cell reaction is [Given that Faraday constant F = 96500 Cmol – 1

Emf of the cell Zn   / Zn + 2 / / Cu + 2 / Cu will be highest when

Which of the following is the best conductor at 298K

Specific conductance is minimum for

For a cell involving one electron, E ° cell = 0 . 59 V at 298 K , the equilibrium constant for the cell reaction is [Given that 2 . 303 RT ¯ = 0 . 059 V atT = 298 K ]

Equivalent conductance at infinite dilution cannot be directly determined for

Molar conductance of 0.01M weak monoprotic acid is 45 mhocm 2 mole – 1 . Molar conductane of the same acid at infinite dilution is 450 mhocm 2 mol – 1 . p H of the acid solution is

During the discharge of lead storage battery, weight of PbSO 4 obtained at cathode involving of 1F of electricity is(At.Wt of Pb = 208)

False statement among the following is

E Pt , 1 2 F 2 / F – 0   =   + 2 .87 V   ;   E Au + 3 / Au 0   =   + 1 .4 V E Fe + 3 / Fe + 2 0   =   + 0 .772 V ;     E Cu + / Cu o   = +   0 .52 V Based on the above data the best oxidant is

Formation of rust is an electrochemical phenomenon. Formula of rust is

The pressure of H 2 required to make the potential of H 2 electrode zero in pure water at 298 K

Aqueous solution of which of the following compounds is the best conductor of electric current?

At 25°C molar conductance of 0.1 molar aqueous solution of ammonium hydroxide is 9 .54   ohm − 1 cm 2 mol − 1 and at infinite dilution its molar conductance is 238   ohm − 1 cm 2 mol − 1 The degree of ionisation of ammonium hydroxide at the same concentration and temperature is

A button cell used in watches function as following. Zn s + Ag 2 O s + H 2 O l ⇌ 2 Ag s + Zn aq 2 + + 2 OH aq − If half cell potentials are Zn aq 2 + + 2 e − Zn s ; E 0 = − 0 .76 V Ag 2 O s + H 2 O l + 2 e − 2 Ag s + 2 OH aq − , E 0 = 0 .34 V The cell potential will be

A hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of pH = 10 and by passing hydrogen gas around the platinum wire at one atm pressure. The oxidation potential of electrode would be?

The molar conductivity of a 0 . 5 mol / dm 3 solution AgNO 3 with electrolytic conductivity of 5 . 76 × 10 – 3 S cm at 298 K is

During the electrolysis of molten sodium chloride, the time required to produce 0.10 mol of chlorine gas using a current of 3 Amperes.

If the E cell ° for a given reaction has a negative value, which of the following gives the correct relationships for the values of ΔG ° and K eq ?

The number of electrons delivered at the cathode during electrolysis by a current of 1 ampere in 60 seconds is ? (charge on electron = 1 . 60 × 10 – 19 C )

Zinc can be coated on iron to produce galvanized iron but the reverse is not possible. It is because

Which one of the following process is not feasible in an aqueous solution

The number of Faradays (F) required to produce 20g of calcium from molten CaCl 2 (Atomic mass of Ca = 40 g mol – 1 ) is :

On electrolysis of dil. sulphuric acid using Platinum (Pt) electrode, the product obtained at anode will be :

Following limiting molar conductivities are given as λ m ∘ H 2 SO 4 = x Scm 2 mol − 1 λ m ∘ K 2 SO 4 = y Scm 2 mol − 1 λ m ∘ CH 3 COOK = z Scm 2 mol − 1 λ m ∘ ( in Scm 2 mol − 1 ) for CH 3 COOH willbe

Given that ∧ m ∞ = 133 .4 AgNO 3 ∧ m ∞ = 149 .9 ( KCl ) ; ∧ m ∞ = 144 .9 Scm 2 mol − 1 KNO 3 the molar conductivity at infinite dilution for AgCl is:

0.1 F of electricity is passed through aqueous CuSO 4 using copper electrodes. Correct statement regarding the process is

Oxidation potential of 0.1M AgNO 3 solution is E Ag / Ag + o   =   − 0 .8 V

The zinc/silver oxide cell is used in electric watches. The reaction is as following, Zn 2 + + 2 e – Zn ; E ° = – 0 . 760 V Ag 2 O + H 2 O + 2 e – 2 Ag + 2 OH – ; E ° = 0 . 344 V If F is 96 , 500 Cmol – 1 , ΔG ° of the cell will be

Regarding Daniel cell, false statement is

Aqueous solution of CuCl 2 is subjected to electrolysis using Pt electrodes. Then the correct statement is

Aqueous solution of Na 2 SO 4 is subjected to electrolysis using inert electrodes. Then the true statement is

Given E Mg + 2 / Mg o   =   − 2 .37 V   ;   E Cu + 2 / Cu 0   =   + 0 .34 V ;   E Mn + 2 / Mn 0   =   − 1 .18 V E 0 Na + / Na   =   − 2 .71 V Correct decreasing order of reducing power is

Given E Li + / Li o   =   − 3 .05 V and E Al + 3 / Al o   =   − 1 .66 V then the emf of the cell Li s   / Li + 1 M / / Al + 3 1 M / Al s   will    be

Consider the redox reaction, 2 A + 3 aq   + 2 B − aq     2 A + 2 aq     + B 2 aq ;     E cell 0   =   0 .3 V   .. Standard Gibb’s energy Δ 0 G of the reaction will be

E Ni + 2 / Ni 0   =   − 0 .25 V ;     E Pt , 1 2 Cl 2 / Cl − 0   =   + 1 .36 V then the spontaneous reaction involves

Molar ionic conductance at infinite dilution of Al + 3 and SO 4 − 2 are ‘ x ‘ mhocm 2 mol – 1 and ‘ y ‘ mhocm 2 mol – 1 respectively. Equivalent conductance of Al 2 ( SO 4 ) 3 at infinite dilution will be mhocm 2 eq – 1

For a cell involving two electron transfer, E 0   =    0 .59 V at 298K. Equilibrium constant for the cell reaction will be

When aq. AgNO 3 is subjected to electrolysis using inert electrodes, 10.8 grams of silver is deptosited at cathode. Weight of oxygen liberated at anode will be

E M + n / M ° is positive for all the following except when M is

Specific conductivity of 0.01M solution of HX is 10 – 6 mho cm – 1 . Molar conductance of the solution is equal to X mho cm 2 mole – 1 . Value of ‘X’ is equal to

Reduction potential of Silver electrode in contact with 0.01M AgNO 3 solution is ( E Ag + / Ag 0 = + 0 . 8 M )

Debye Huckel equation is not useful to determine molar conductance at infinite dilution for the following electrolyte

Reduction potential of hydrogen electrode is maximum when it is in contact with a solution of

Which one of the following electrolyte does not liberate oxygen at anode during electrolysis

Reduction potential of Zinc Electrode in contact with 0.01M ZnSO 4 is – 0 . 82 V . SRP of Zinc Electrode will be

A galvanic cell is constructed using SHE and another electrode ‘ X ‘ under standard conditions. ‘ X ‘ in this cell is the negative electrode then ‘ X ‘ is

Degree of dissociation of 0.1M weak monoacidic base, BOH is 0 . 2 . Molar conductance at infinite dilution of BOH is 360 mho cm 2 mole – 1 . Molar conductance of decimolar BOH will be ——- mho cm 2 mole – 1

Zn gives H 2 gas with dil.H 2 SO 4 and HCl but not with dil.HNO 3 because

Daniel cell is shown as

25 mL of HCl solution is titrated with 0.10 mole L –1 NaOH solution in a conductivity cell. The data obtained were plotted to give the graph shown below The concentration of HCl solution is

Molten sodium chloride conducts electricity due to the presence of

An electronic conductor is

Which of the following is conductor of electricity

Sodium metal in liquid ammonia is

LIST – 1 LIST – 2 A) Electronic conductor 1) Aqueous urea solution B) Non-electrolyte 2) Solid sodium C) Electrolytic dissociation 3) Electrolytic conductor D) Arrhenius 4) Radioactivity increases 5) Conductivity raises with temperature The correct match is

Which of the following is 100% ionised at any dilution ?

Reason for increase in electrical conduction of electrolyte with increase in temperature is A) increase in the number of ions B) increase in the speed of ions C) increase in the degree of dissociation of electrolyte

Choose the wrong statement

Which of the following (1M) conducts more electricity ?

The degree of dissociation of an electrolyte in aqueous solution depends on A) Temperature B) Concentration of the electrolyte C) Nature of the electrolyte

At infinite dilution the degree of dissociation for sucrose in aqueous solution is

What happens at infinite dilution in a given solution ?

Choose the correct statement regarding electrolytic cell

The following are some statements about electrolytic cell A) in this, chemical energy converted into electrical energy B) in this cell, electrons flow from cathode to anode C) in this, cell reduction takes place at cathode D) in this, cathode is a +ve electrode The correct combination is

The products formed when an aqueous solution of NaBr is electrolysed in a cell having inert electrodes are

When an aqueous solution of lithium chloride is electrolysed using graphite electrodes

A dilute aqueous solution of Na 2 SO 4 is electrolysed using platinum electrodes. The products at the anode and cathode are

The products of electrolysis of aqueous NaCl solution are

The reactions taking place at anode and cathode are

The electrode through which the electrons enter the electrolytic solution is

In the electrolytic cell, flow of electrons is from

When as electrolysis is in progress, if the cathode plate is removed

Which process occurs in the electrolysis of aqueous solution of nickel chloride at nickel anode?

In electrolysis of dilute H 2 SO 4 , which is liberated at anode in presence of inert electrode ?

Molten CuCl 2 is electrolysed using platinum electrode. The reaction occuring at anode is

During the electrolytic reduction of alumina, the reaction at cathode is

Aqueous solution of CuSO 4 is electrolysed using inert electrodes till the blue coloured solution becomes colourless. The colourless solution formed is

After the electrolysis of aqueous solution of NaCl using Pt electrodes, the pH of the solution

When an aqueous solution of copper sulphate is electrolysed using copper electrodes the reaction at the anode is represented by

Which of the following reaction is possible at anode ?

During the electrolysis of aqueous solution of the following, molarity of the solution increases without changing the chemical composition

Aqueous NaCl solution is electrolyzed using platinum electrodes. What is the product formed at cathode?

At anode in the electrolysis of fused sodium chloride

Which of the following ions is obtained at the cathode when an aqueous solution of sodium hydroxide is electrolysed ?

During electrolysis of fused NaOH

Aqueous solution of AgNO 3 is electrolysed using inert electrodes. At the end of electrolysis

Electrolysis of dilute aqueous NaCl solution was carried out by passing 10 milli ampere current. The time required to liberate 0.01 mol of H 2 gas at the cathode is (1 Faraday = 96500 C mol -1 )

An aqueous solution containing one mole per litre of each Cu(NO 3 ) 2 , AgNO 3 . Hg(NO 3 ) 2 , Mg(NO 3 ) 2 is being electrolysed using inert electrodes. The values of standard electrode potential in volts (reduction potential) are Ag / Ag + = + 0.80V Hg 2+ / Hg = + 0.79V Cu 2+ / Cu = + 0.34V Mg 2+ / Mg = – 2.37V With increasing voltage, the sequence of deposition of metals on cathode will be

According to Faraday's first Law of electrolysis mass of substance liberated is equal to

At cathode, the electrolysis of aqueous Na 2 SO 4 gives

In the electrolysis of aqueous sodium chloride solution, Which of the half cell reaction will occur at anode ?

When a quantity of electricity is passed through CuSO 4 solution 0.16g of copper gets deposited. If the same quantity of electricity is passed through acidulated water. Then the volume of H 2 liberated at STP will be [given : at.wt.of Cu = 64]

According to 2nd law of Faraday’s electrolysis the correct one is The correct combination is

For the discharge of equal masses of the following ions, the number of electrons required is maximum in the case of

When the same charge is passed through the solutions of different electrolytes in series, the amounts of elements deposited on the electrodes are in the ratio of their

One Faraday is equal to

One Faraday of electricity will liberate 1 gram atom of the metal from the solution of

The emf of the following three galvanic cells are represented by E 1 , E 2 and E 3 respectively. Which of the following is correct ? (i) Zn/Zn 2+ (1M)//Cu 2+ (1M)/Cu (ii) Zn/Zn 2+ (0.1M)//Cu 2+ (1M)/Cu (iii) Zn/Zn 2+ (1M)//Cu 2+ (0.1M)/Cu

The minimum conductance in fused state is shown by

SI units of molar conductance are

The unit of equivalent conductivity is

LIST – 1 LIST – 2 A) One faraday 1) Reduction B) Anode 2) 96500 coulomb C) Cathode 3) 6.24 × 10 18 electrons D) 1 coulomb 4) Oxidation 5) Z × 96,500

The value of molar conductivity of HCl is greater than that of NaCl at a particular temperature because

The weight of hydrogen deposited at cathode when 965 amperes current is passed for 100 seconds through acidulated water is

By passing electric current, NaClO 3 is converted in to NaClO 4 according to the following equation .How many moles of NaClO 4 will be formed when three faradays of charge is passed through NaClO 3 ?

The unit of specific conductivity is

The highest electrical conductivity of the following aqueous solutions is of

The electrochemical equivalent of a metal is "x"g. coulomb –1 . The equivalent weight of metal is

If the specific conductance and conductance of a solution is same, then its cell constant is equal to

Specific conductivity of a solution

The weight in grams of O 2 formed at Pt anode during the electrolysis of aq. K 2 SO 4 solution during the passage of one coulomb of electricity is

A graph is drawn between the λ eq values and concentrations of an electrolyte. Which of the following electrolyte will correspond to the graph given ?

The equivalent conductance of 1N solution of an electrolyte is nearly

If the molar conductance values of Ca 2+ and Cl – at infinite dilution are respectively 118.88 × 10 -4 m 2 mho mol -1 and 77.33 × 10 -4 m 2 mho mol -1 , then that of CaCl 2 is (in m 2 mho mol -1 )

What current is to be passed for 0.25 s for deposition of a certain weight of metal which is equal to its electrochemical equivalent ?

A solution of concentration 'C' g equiv/litre has a specific resistance R. The equivalent conductance of the solution is

The expression showing the relationship between equivalent conductivity and molar conductivity is

According to Kohlrausch law, the limiting value of molar conductivity of an electrolyte A 2 B is

Degree of dissociation of pure water is 1.9 × 10 -9 . Molar ionic conductances of H + and OH – ions at infinite dilution are 200 S cm 2 mol -1 and 350 S cm 2 mol -1 respectively. Molar conductance of water is

Which of the following is not a conductor of electricity?

For which case λ values v/s C shows a straight line

The distance between two electrodes of a cell is 2.5 cm and area of each electrode is 5 cm 2 the cell constant (in cm –1 ) is

The molar conductivities λ NaOAc 0 and λ HCl 0 at infinite dilution in water at 25 0 C and 91.0 and 426.2 S cm 2 / mol respectively. To caculate λ HOAc 0 the additional value required is

The ionic conductance of the following cations in a given concentration are in the order

At T(K) the molar ionic conductivities of NH 4 + and OH – at infinite dilution are 72 and 198 Scm 2 mol –1 respectively. The molar conductivity of 0.01M NH 4 OH solution at the same temperature is found to be 9 Scm 2 mol –1 . The percentage dissociation of NH 4 OH at this concentration is

The effect of temperature increase on conduction is as follows

The cell reaction of the galvanic cell, Cu (s) / Cu 2+ (aq) // Hg 2+ (aq) / Hg (l) is

The equation representing Kohlrausch law from the following is

The ionic conductance of which of following ion in fused state is low

Stronger the oxidising agent greater is the

If the cell reaction is spontaneous

The correct order of equivalent conductance at infinite dilution of LiCl, NaCl and KCl is

Which metal will dissolve if the cell notation is Cu | Cu 2+ || Ag + | Ag

Standard reduction electrode potential of three metals A, B and C are respectively + 0.05 V, – 3.0 and – 1.2 V. The correct order of reducing power is

The function of a salt bridge is

The difference of potential of two electrodes in a galvanic cell is known as

The standard electrode potentials of four metals A, B, C and D are – 2.65, – 1.66, – 0.80 and + 0.86 V. The highest chemical activity will be exhibited by the metal

At 298 K the standard reduction potentials for the following half reactions are given as The strongest reducing agent is

Zn gives H 2 gas with H 2 SO 4 and HCI but not with HNO 3 because

Standard electrode potentials are Fe 2+ , Fe 3+ and Fe blocks are kept together, then

When Zn piece is kept in CuSO 4 solution, copper gets precipitated because :

The hydrogen electrode is dipped in a solution of pH = 3 at 25 0 C. The potential of the cell would be (value of 2.303 RT/F is 0.059 V)

Which reaction is not feasible ?

Beryllium is placed above magnesium in the II group. When beryllium dust is added to MgCl 2 solution, will

For I 2 + 2 e 2 I – , standard reduction potential = + 0.54 volt. For 2 Br – Br 2 + 2 e – , standard oxidation potential = – 1.09 volt. For Fe Fe 2 + + 2 e – standard oxidation potential = + 0.44 volt. Which of the following reactions is non-spontaneous?

E° for is –0.44 V E° for is –0.76 V. Then

The more electropositive element has

Four colourless salt solutions are placed in separate test tubes and a strip of copper is placed in each. Which solution finally turns blue?

A smuggler could not carry gold by depositing iron on the gold surface since

The E 0 of the cell is 2.12 V. To increase E

The e.m.f. of the given Daniel cell at 298 K is E 1 Zn /ZnSO 4 (0.01M)//CuSO 4 (1.0M)/Cu When the concentration of ZnSO 4 is 1.0 M and that of CuSO 4 is 0.01M, the e.m.f. changed to E 2 . What is the relationship between E 1 and E 2 ?

The Nernst equation for the reduction potential of a non metal A when [A n- ] = C is given by

For the cell Zn/Zn 2+ //Cu 2+ /Cu, if the concentration of Zn 2+ and Cu 2+ ions is doubled, the emf of the cell

For a cell reaction, of an electrochemical cell, the change in standrad free energy, at a given temperature is

For a spontaneous reaction the ΔG , equilibrium constant (K) and E 0 cell will be respectively

For the reaction Pt /H 2 (1atm) / H + (aq) // Cl – (aq) /AgCl/Ag K c (equilibrium constant) is represented as

The potential of standard hydrogen electrode is zero. This implies that

Which of the following is not correct ?

The correct relationship between free energy change in a reaction and the corresponding equilibrium constant K C is

The standard reduction potentials of three electodes P, Q and R are respectively – 1.76 V, 0.34 V and 0.8 V. Then

The Nernst equation giving dependence of electrode potential on concentration is

A lead storage battery has been used for one month (30 days) at the rate of one hour per day by drawing a constant current of 2 amperes. H 2 SO 4 consumed by the battery is

When lead storage battery is charged

Galvanization process includes plating iron with

The metal that cannot displace hydrogen from dilute hydrochloric acid is

In a fuel cell, methanol is used as fuel and oxygen gas is used as an oxidizer. The reaction is CH 3 OH ( l ) + 3 2 O 2 CO 2 ( g ) + 2 H 2 O ( l ) At 298K, standard Gibbs energies of formation for CH 3 OH (l) , H 2 O (l) and CO 2(g) are –166.2, –237.2 and –394.4 KJ respectively. If standard enthalpy of combustion of methanol is –726 KJ, efficiency of the fuel cell will be

A secondary cell is one

Corrosion is basically a/an

Zinc is used to protect corrosion of iron because

In which of the following will the corrosion of iron be most rapid ?

Corrosion is chemically

The composition of rust is

Which of the following solutions of NaCl has the higher specific conductance ?

On passing current through molten KCl, 19.5 g of K is deposited. The amount of Al deposited by the same quantity of electricity when passed through molten AlCl 3 is

The number of electrons involved in the electro deposition of 63.5 g. of Cu from a solution of CuSO 4 is

Same amount of electric current is passed through solutions of AgNO 3 and HCl. If 1.08 g of silver is obtained in the first case, the volume of hydrogen liberated at S.T.P. in the second case is

On passing 3F electricity through three cells containing fused Na 2 CO 3 , fused Cu(NO 3 ) 2 and fused Al(NO 3 ) 3 , the number of moles of the metals deposited are in the ratio

By passing 0.1 Faraday of electricity through fused sodium chloride, the amount of chlorine liberated is

The current strength required to displace 0.1 g. of H 2 in 10 sec is

The amount of chlorine evolved when 2 amperes of current is passed for 30 minutes through aqueous solution of NaCl is

Weight of copper (atomic mass 63.5) deposited when 2 Faradays of electricity is passed through cupric salt solution is

If three faradays of electricity are passed through the solutions of AgNO 3 , CuSO 4 and AuCl 3 , the molar ratio of the cations deposited at the cathode will be

On electrolysing a sample of acidified water, 22.4 ml of hydrogen was obtained. The volume of oxygen in ml obtained is

The electro chemical equivalent of an element is 0.0006735 g/C. Its equivalent weight is

When electricity is passed through molten AlCl 3 , 13.5 g. of Al is deposited. The number of Faradays of electricity passed will be

When 6 ×10 22 electrons are used in the electrolysis of a metallic salt, 1.9 gm of the metal is deposited at the cathode. The atomic weight of that metal is 57. So oxidation state of the metal in the salt is

Four moles of electrons were transferred from anode to cathode in an experiment on electrolysis of water. The total volume of the two gases (dry and at STP) produced will be approximately (in litres)

When 3.86 amperes current are passed through an electorlyte for 50 minutes, 2.4 grams of a divalent metal is deposited. The gram atomic weight of the metal (in grams) is

For the electrolytic production of NaClO 4 from NaClO 3 according to the equation NaClO 3 + H 2 O NaClO 4 + H 2 the number of Faradays of electricity required to produce 0.5 mole of NaClO 4 is

What is the quantity of electricity (in coulombs) required to deposit all the silver from 250 ml of 1 M AgNO 3 solution ?(Ag = 108)

When 965 amp current is passed through aqueous solution of salt X using platinum electrodes for 10 sec, the volume of gases liberated at the respective electrodes is in 1:1 ratio. Then X is

The amount of current in Faraday is required for the reduction of 1 mol of Cr 2 O 7 –2 ions to Cr 3+ is,

Specific conductance of 0.1 M Nitric acid is 6.3 × 10 –2 ohm –1 cm –1 . The molar conductance of the solution is

The values of equivalent conductivity at infinte dilutions for NH 4 Cl, NaOH and NaCl are respectively 149.74, 248.1 and 126.4 ohm –1 cm 2 equi –1 . The value of λ eq ∞ of NH 4 OH is ————ohm -1 cm 2 eq -1

0.05M NaOH solution offered a resistance of 31.6 Ω in a conductivity cell at 298K. If the cell constant of the conductivity cell is 0.367cm –1 , the molar conductivity of the NaOH solution is

Molar ionic conductivities of a bi-bivalent electrolyte are 57 and 73. The molar conductivity of the solution will be

At 25 0 C the molar conductances at infinite dilution for the strong electrolytes NaOH, NaCl and BaCl 2 are 248 × 10 –4 , 126 × 10 –4 and 280 × 10 –4 S.m 2 mol –1 respectively. λ m 0 Ba(OH) 2 in s.m 2 mol –1 is

For a cell reaction involving a two-electron change, the standard e.m.f. of the cell is found to be 0.295 V at 25 0 C. The equilibrium constant of the reaction at 25 0 C will be

, The EMF of the cell, Zn | Zn 2+ (0.1M) || Cu 2+ (0.01M) | Cu is

The potential of the cell containing two hydrogen electrodes as represented below Pt, H 2(g) | H + (10 -6 M) || H + (10 -4 M)|H 2(g) , Pt at 298 K is

HA is a weak electrolyte. At 25 0 C, the degree of dissociation of 0.5 mol L –1 HA is 0.1. What is its molar conductivity (in S cm 2 mol –1 ) ? (The limiting molar conductivity of HA is,390 S cm 2 mol –1 )

, The cell reaction of the cell constructed from these two electrodes is

Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0.1M is 100 Ω .The conductivity of this solution is 1.29 S m –1 . Resistance of the same cell when filled with 0.02M of the same solution is 520 Ω . The molar conductivity of 0.02M solution in Sm 2 mol –1

If the standard electrode protential of Cu 2+ / Cu electrode is 0.34 V, what is the electrode potential at 0.01 M concentration of Cu 2+ ? (T = 298 0 K)

Consider the following E 0 values E 0 Fe 3+ / Fe 2+ = + 0.77 V E 0 Sn 2+ / Sn = – 0.14 V Under standard conditions the potential for the reaction is

The standard reduction potentials of Zn 2+ | Zn and Cu 2+ | Cu are –0.76 V and + 0.34 V respectively. What is the cell e.m.f (in V) of the following cell? Zn | Zn 2+ (0.05 M || Cu 2+ (0.005 M | Cu.

A cell constructed by coupling a standard copper electrode and a standard magnesium electrode has emf of 2.7 volts. If the standard reduction potential of copper electrode is +0.34 volt, that of magnesium electrode is

Standard electrode potentials of and are – 0.440V and – 0.036V respectively. The standard electrode potential (E°) for is

EMF of a cell in terms of reduction potential of its left and right electrodes is

Statement I : At moderate concentrations molar conductivity of KCl is greater than that of CH 3 COOH Statement II : At moderate concentrations, KCl completely ionizes whereas CH 3 COOH undergoes incomplete ionisation

Statement I : Limiting molar conductance of 0.1M HCl is greater than that of 0.1M NaCl Statement II : Ionic conductance of H + ion is greater than that of Na + ion

Statement I : Surface of a metal acts like an electrochemical cell Statement II : Oxygen concentration on the surface a metal is not uniform

Statement I : Passage of same quantity of electricity deposits more amount of copper from aq.Cu 2 Cl 2 than from aq. CuSO 4 Statement II :Eq.wt of copper is more in CuSO 4 than in Cu 2 Cl 2

The emf of a Daniel cell at 298K is E 1 Zn | ZnSO 4(0.01M) || CuSO 4(1.0M) | Cu when the concentration of ZnSO 4 is 0.1 M and that CuSO 4 is 0.01 M, the emf changed to E 2 . What is the relationship between E 1 and E 2

Standard free energies of formation (in kJ/ mol) at 298 K are – 237.2, – 394.4 and – 8.2 for H 2 O(l), CO 2 (g) and pentane (g), respectively. The value of E cell 0 for the pentane-oxygen fuel cell is :

Given : (i) Cu +2 +2e – Cu, E 0 = 0.337V (ii) Cu +2 +e – Cu + , E 0 = 0.153V Electrode potential, E 0 for the reaction,Cu + + e – Cu, will be

For the reduction of silver ions with copper metal, the standard cell potential is 0.46 V at 25 0 C. The value of standard Gibbs energy ∆ G 0 will be

The number of electorns delivered at the cathode during electrolysis by a current of 1 ampere in 60 seconds is (charge on electron = 1.60 × 10 –19 C)

Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below Then the species undergoing disproportionation is

The time period to coat a metal surface of 80 cm 2 with 5 × 10 –3 cm thick layer of silver (density 1.05 g cm –3 ) with the passage of 3A current through a silver nitrate solution is

A factory produces 40 kg of calcium in two hours by electrolysis. How much aluminium can be produced by same current in 2 hours if current efficiency is 50%?

Conductance of Al +3 is ‘x’ Sm 2 geq -1 and that of SO 4 -2 is ‘y’ Sm 2 geq -1 . molar conductance of Aluminium sulphate is…..Sm 2 mole -1

At 298 K and 1 atm a copper electrode is in contact with 0.1 M CuSO 4 solution. Which of the following graphical representation is correct for E Cu + 2 / Cu ( y – axis ) Vs log Cu + 2 ( x – axis )

Molar conductance of 0.1 M weak mono basic acid(HA) is 36 mho . cm 2 . mole – 1 . At the same temperature, molar conductance of HA at infinite dilution is 360 mho . cm 2 . mole – 1 . p H of HA will be

Oxygen and hydrogen gases are produced at the anode and cathode respectively during electrolysis of dilute aq. solution of:

Which one of the following is the best oxidizing agent in aqueous solution? E Na + / Na o = − 2 .71 V ; E 1 2 Cl 2 / Cl − o = + 1 .36 V ; E 1 2 I 2 / I − o = + 0 .54 V ; E Al + 3 / Al o = − 1 .66 V ;

‘A’ is a strong electrolyte. ‘B’ is a weak electrolyte. Decimolar solutions of ‘A’ and ‘B’ are taken in two separate vessels at same temperature. On diluting both these electrolytes to the same extent, correct statement of the following is

Faraday gave quantitative relation between current passed and mass of the substance deposited or liberated at a particular electrode. Units of electrochemical equivalent are

Faraday gave quantitative relation between current passed and the mass of the substance deposited at a particular electrode. Units of electrochemical equivalent are

Regarding batteries, some reactions are given below. The false combination is

Zn gives H 2 gas with H 2 SO 4 and HCl but not with HNO 3 because

Difference in Λ m o of KCl and NaCl is ‘X’ mho    cm 2    mole − 1 . Difference in Λ m o of KNO 3 and NaNO 3 is ‘Y’ mho    cm 2    mole − 1 . Correct relation between ‘X’ and ‘Y’ is

Aqueous solution of AgNO 3 is subjected to electrolysis using Pt electrodes. False statement about the process is

18 grams of acidulated water is subjected to electrolysis using 965 amperes. Time required for electrolysis is

p H of an acid solution in contact with hydrogen electrode is two. Reduction potential of Hydrogen electrode is

Reduction potential of chlorine electrode in contact with 0.01 M HCl solution is E Pt , Cl 2 / Cl – o = + 1 .36   V

For unimolar solution of uni-univalent electrolyte, the correct relation between equivalent conductance ( mho . cm 2 . g eq – 1 ) and specific conductance ( mho . cm – 1 ) is

Debye-Huckel’s equation is given as Λ c = Λ 0 – A C . It is useful to determine molar conductance at infinite dilution for all the following electrolytes except

Correct statement among the following is

Electro chemical equivalent of an element is 9 . 33 × 10 – 5 g / mol . Equivalent weight of the element is

The anodic reaction in dry cell is

Reagarding dry cell, the incorrect statement is

A silver electrode in contact with 1M AgNO 3 solution is diluted by 100 times. The true statement about the process is

At 298 K, molar conductance of 0.1 M weak monoacidic base (BOH) is 45 mho.cm 2 .mole -1 . Molar conductance of BOH at infinite dilution is 450 mho.cm 2 .mole -1 . p H of deci molar solution of BOH is

Cell notation of Daniel cell is Zn s / Zn 2 + 1 M / / Cu 2 + 1 M / Cu s . Standard free energy change for the reaction occurring in Daniel cell is E Zn 2 + / Zn 0 = – 0 . 76 V , E Cu 2 + / Cu 0 = + 0 . 34 V

Cell notation of a galvanic cell is Fe s Fe + 2 C 1 Ag + C 2 Ag s . Emf of the cell is maximum when C 1   :   C 2 2 is

The incorrect statement about electrochemistry is

Zn ( s ) + Cu 2 + ( aq ) Zn 2 + ( aq ) + Cu ( s ) The above redox reaction is used in

In general, in a Galvanic cell

What happens when applied external opposite potential in a Daniell cell reaches to 1.1 V?

When applied external opposite potential in case of Daniell cell is less than 1.1 V, then

Look at the Daniell cell. The incorrect statement related to this cell is

Electrolytic cell is a device

select the false statement for Daniell cell.

The electrode potential is known as standard electrode potential

Select the correct statement(s) for the Galvanic cell.

The correct cell representation of the following cell is Zn + 2 Ag + Zn 2 + + 2 Ag

Select the incorrect statement.

In the cell representation.

Calculate the standard cell potential for the following Galvanic cell, Cr Cr 3 + Cd 2 + Cd Given , E Cr 3 + / Cr o = – 0 . 74 V and E Cd 2 + / Cd o = – 0 . 40 V

The reduction potential of hydrogen half-cell will be negative if

Pt ( s ) H 2 g , 1 bar H + aq , 1 M Cu 2 + aq , 1 M Cu The measured emf of the cell is 0.34 V means

Select the correct statement for the cell Pt ( s ) H 2 g , 1 bar H + aq , 1 M Zn 2 + aq , 1 M Zn Given, Zn 2 + / Zn = – 0 . 76 V

If the standard electrode potential of an electrode is greater than zero then

Standard electrode potential of three metals X Y and Z are -1.2 V, + 0.5 V and -3.0 V respectively. The reducing power of these metals will be

For the reaction, M n + aq + ne – M ( s ) , select the best suitable representation of Nernst equation, when the solid M is taken.

Given, E I 2 / I – o ( 1 M ) = + 0 . 54 V , and E Br 2 / Br – o ( 1 M ) = 1 . 09 V On this basis the feasible reaction is

Select the strongest reducing agent from the given electrode potential.

Select the most appropriate Nernst equation for Daniell cell containing Cu 2 + and Zn 2 + ions .

Compound XA, XB, XC are added into separate test tubes containing A, B, C solutions. XB react with A and C. XA does not react with any of these. XC reacts with A. Arrange the anion in the decreasing order of their oxidation.

Select the appropriate statement for Daniell cell containing Cu 2 + and Zn 2 + ions .

The electrode potentials for Cu 2 + aq + e – Cu + aq and Cu + aq + e – Cu s are + 0 . 15 V and + 0 . 50 V respectively. The value of E Cu 2 + / Cu o will be.

The correct statement about conductivity is

Which of the following statement is correct?

Organic conducting polymers are

Select the appropriate statement(s) about ionic conductance.

Select the incorrect statement.

Alternating current (AC) is used instead of direct i current (DC) for the measurement of conductivity of ionic solutions. This is because

Conductivity decreases with decrease in concentration or weak as well as strong electrolytes. This is because

Select the correct statement.

The conductance of electrolytic solution kept between the electrodes of conductivity cell at unit distance but having area of cross-section large enough to accommodate sufficient volume of solution is called

Select the incorrect statement.

In order to obtain pure copper from impure copper by electrolysis

Which of the following statements is/are incorrect for electrolytic cell?

For the cell, Cu Cu 2 + ∥ Ag + Ag , E cell ∘ = + 0 .46 V If concentration of Cu 2+ ions is doubled, then E cell o will be

Standard electrode potential for Sn 4 + / Sn 2 + couple is +0. 15V and that for the Cr 3 + / Cr couple is – 0.74 V. These two couples in their standard state are connected to make a cell. The cell potential will be

A hydrogen gas electrode is made by dipping platinum wire in a solution of HCI and pH = 10 and by passing hydrogen gas around the platinum wire at 1 atm pressure. The oxidation potential of electrode would be

A button cell used in watches, functions as following Zn ( s ) + Ag 2 O ( s ) + H 2 O ( l ) ⇌ 2 Ag ( s ) + Zn 2 + ( , ) + 2 OH − ( aq ) If half-cell potentials are Zn 2 + ( aq ) + 2 e − ⟶ Zn ( s ) ; E ∘ = − 0 .76 V Ag 2 O ( s ) + H 2 O ( l ) + 2 e − ⟶ 2 Ag ( s ) + 2 OH − E ∘ = 0 .34 V the cell potential will be

Equilibrium constant (K) is related with standard cell potential ( E cell o ) but not with E cell . This is because

Consider the following cell reaction 2 Fe ( s ) + O 2 ( g ) + 4 H + ( aq ) ⟶ 2 Fe 2 + ( aq ) + 2 H 2 O ( l ) , E ∘ = 1 .67 V At Fe 2 + = 10 − 3 M , p O 2 = 0 .1 atm and pH = 3 , the cell potential at 25 o C is

Calculate the equilibrium constant for the reaction, Zn ( s ) + Cu 2 + ( aq ) ⟶ Zn 2 + ( aq ) + Cu ( s ) Given, E cell ∘ = 1 .1 V

Which of the following statements is/are incorrect?

The graph of molar conductivity versus C 1 / 2 is plotted. Which type of electrolyte are used in A and B ?

Consider the following graph. Here the limiting molar conductivity is

Select the correct statement for Λ m = Λ m ∘ − AC 1 / 2 .

Two electrolytes X and Y are diluted. Λ m of I increases 1.5 times and for X it increase 25 times. Predict the strong electrolyte among X and Y .

“Limiting molar conductivity of an electrolyte can be represented as sum of the individual contributions of anion and cation of the electrolyte”. Which law states the above statement ?

Calculate the limiting molar conductivity of NaCl and KBr from the above table Ion Λ ∘ S cm 2 mol − 1 Ion Λ ∘ S cm 2 mol − 1 H + 349.6 OH – 199.1 Na + 50.1 CI – 76.3 K + 73.5 Br – 78.1 Ca 2+ 119.0 CH 3 COO – 40.9 Mg 2+ 106.0 SO 4 2 – 160.0

The limiting molar conductivity of calcium acetate is

If the E cell o for a given reaction has a negative value, then which of the following gives the correct relationships for the values of ∆ G o and K eq ?

What will be the weight of silver deposited, if 96.5 A of current is passed into aqueous solution of AgNO 3 for 100 s?

When 0.1 mole of MnO 4 2 – is oxidised, the quantity of electricity required to completely oxidise MnO 4 2 – to MnO 4 –

Statement 1 :Platinum and gold are used as inert electrodes. Statement 2 : Pt and Au do,not participate in the reaction and provide the surface for oxidation or reduction

Statement 1 :Conductivity always increases with decrease in concentration for strong and weak electrolytes. Statement 2 : Number of ions per unit volume decreases on dilution.

Statement 1 :Conductivity of electrolytes decreases when dissolved in water. Statement 2 : They furnish their own ions.

Statement 1 : Conductivity of pure water is 3 . 5 × 10 – 5 S m – 1 . Statement 2 : High amounts of hydrogen and hydroxyl ions are present in water.

Statement 1 : Anhyd. HCI is bad conductor of electricity, while aq. HCI is good conductor. Statement 2 : Aqueous HCI is not fully ionised but anhyd. HCl is ionised to produce H + and Cl – .

Statement 1 : Electrolysis of NaCl solution gives chlorine at anode instead of O 2 . Statement 2 : Formation of oxygen at anode requires over voltage.

Statement 1 : Impure copper is converted into pure copper by electrolysis. Statement 2 : Copper is dissolved at cathode and deposited at anode.

Statement 1 : Mercury cells give a constant voltage throughout its life. Statement 2 : Electrolyte KOH is not involved in the reaction.

Statement 1 : A solution of Ni(NO 3 ) 2 is electrolysed between platinum electrodes using current of 5 A for 20 minute. The weight of Ni deposited is 1.825 g. Statement 2 : The mass of substance deposited during the electrolysis of an electrolyte is inversely proportional to the quantity of electricity passed through the electrolyte.

Match the following Column I with type of electrolyte in Column II and choose the correct option from the codes given below. Column I Column II A. NaCl 1. 2-1 electrolyte B. CaCl 2 2. 2-2 electrolyte C. MgSO 4 3. 1 – 1 electrolyte

Match the following Column I (expressions) with Column II and choose the correct option from the codes given below. Column I Column II A. ρl / A 1. Conductivity B. 1/R 2. Conductance C. RA/l 3. Resistance D. 1 / ρ 4. Resistivity

Mark the incorrect statement(s) for fuel cells.

A device that converts energy of combustion of fuels like hydrogen and methane, directly into electrical energy is known as

Mark the incorrect statement about corrosion.

Statement 1 : Magnesium blocks are fixed to the bottom of ship. Statement 2 : Magnesium acts as sacrificial electrode.

During the rusting of iron

Given the standard electrode potentials. E Fe 2 + / Fe ∘ = − 0 .44 V and E H + / O 2 / H 2 O ∘ = 1 .23 V

An electrolytic cell contains alumina. If we have to obtain 50 g Al by using 105 A of current, the time required is

1.5 A current is flowing through a metallic wire. If it flows for 3 hrs, how many electrons would flow through the wire?

How many coulombs are required in order to reduce 12.3 g of nitrobenzene to aniline?

6 A current with 75% efficiency is passed through a cell for 6 h? ( z = 4 x 10 -4 ). The amount of metal deposited will be

Same amount of electricity is passed through the solutions of HCl and CuSO 4 . If 6.35 g of copper is deposited from CuSO 4 solution, the amount of hydrogen liberated at STP will be

10 F of electricity is passed through the solutions of silver nitrate, copper sulphate and ferric chloride. The amount of metal deposited at cathode in each case respectively are

Which of the following products are formed at cathode and anode during the electrolysis of an aqueous solution of MgSO 4 between inert electrodes?

Select the incorrect statement.

Which of the following statement is incorrect for dry cell ?

What is the anode and cathode in the cell given in the figure?

When an external opposite potential greater than 1.1 V is applied to the Galvanic cell

Select the incorrect statements.

Select the correct statements.

The correct statements among the following is

Select the incorrect statements.

When very dilute solution of sodium hydroxide is electrolysed using platinum electrodes, then

What happens when opposing voltage is applied to the Galvanic cell reaches 1.1 V ? I. Reactions stop together. II. No current flows through the cell. III.Rate of reaction increases. Which of the above statements is/are correct ?

I. The potential of individual half-cell can be measured. II. Difference between the potentials of two half-cells can only be measured. III. Pt ( s ) H 2 g H + aq half – cell is called standard hydrogen electrode. Select the correct statement(s) and choose the appropriate option

I.Q = It II. Charge required for oxidation or reduction depends on the stoichiometry of electrode reaction. III. Charge on 1 electron – 1.6021 x 10 -19 C IV. Charge on I mole of electron = 1.6021x 10 -19 C V. Unit of current is Coulomb (C) VI. 1F= 96500 C mol -1 Which of the following statements are incorrect?

Some organic substances are conducting polymers. The true statement(s) regarding them is/are I. These being lighter are used to make light weight batteries. II. Being flexible these are used to make electronic devices like transistors

Consider the following statements. I. In dry cell, a moist paste of NH 4 Cl and ZnCl 2 is present in between the electrodes. II. Ammonia gas is produced in Leclanche cell. III. A part of KOH and ZnO is used as electrolyte in mercury cell. True statements are

I. Rusting of iron is an example of corrosion but tarnishing of sodium metal is not. II. Covering the surface with bis – phenol protect iron from rusting. III. Sn and Zn are used to protect iron from rusting. True statements are

Match the following columns. Column I Column II A Zn + Cu 2 + ⟶ Cu + Zn 2 + p Cathode half reaction is Cu 2 + + 2 e − ⟶ Cu B Mg + Cu 2 + ⟶ Cu + Mg 2 + q Electrons flows from metal to Cu side. C 2 Ag + + Cu ⟶ Cu 2 + + 2 Ag r E anode ∘ < E cathode ∘ D H 2 + Cu 2 + ⟶ H + + Cu s Hydrogen electrode is used

Match the salts given in Column I with their use given in Column II. Column I Column II A. Hg 2 Cl 2 p. Salt bridge B. Agar-Agar q. Calomel electrode C. 0.1 N KCl r. Ice cream D. Quinhydron s. Redox electrode

Match the physical quantities given in Column I with their units given in Column II. Column I Column II A. Resistance p. Ω B. Resistivity q. volt / A − 1 C. Conductivity r. Ωm D. Specific conductance s. Ω − 1 m − 1

Directions of current is from

The reaction which occur in the Galvanic cell is MnO 4 − + 8 H + + 5 Fe 2 + ⟶ Mn 2 + + 5 Fe 3 + + 4 H 2 O E ∘ MnO 4 − , Mn 2 + , H + ∣ Pt = 1 .51 V and E ∘ Fe 3 + , Fe 2 + ∣ Pt = 0 .77 V (Q) Calculate the standard emf of cell.

The reaction which occur in the Galvanic cell is MnO 4 − + 8 H + + 5 Fe 2 + ⟶ Mn 2 + + 5 Fe 3 + + 4 H 2 O E ∘ MnO 4 − , Mn 2 + , H + ∣ Pt = 1 .51 V and E ∘ Fe 3 + , Fe 2 + ∣ Pt = 0 .77 V (Q) How would the emf of the cell be increased above the standard emf ?

Calculate the conductivity of 0.2 mol L -1 KCI solution.

A 4.0 M aqueous solution of NaCl is prepared and 500 mL of this solution is electrolyzed. This leads to evolution of chlorine gas at one of the electrodes. (Q). The total charge required for the complete electrolysis will be

How many grams of Cu is deposited by passing 6F through aqueous CuSO 4 solution in presence of inert electrodes.

NaCl aqueous solution on electrolysis gives H 2 ( g ) , Cl 2 ( g ) and NaOH . 2 Cl − ( aq ) + 2 H 2 O ⟶ 2 OH − ( aq ) + H 2 ( g ) + Cl 2 ( g ) . In 20 L of NaCl solution (20% by weight), current of 25. A with 62% of current efficiency is passed. Which of the following reaction will occur at anode?

What is the amount of electricity required (experimentally) in terms of Faraday to get 1 kg of Cl 2 from 20 Lit of 20 % by weight of NaCl aqueous solution by passing a current of 25 A with 62 % current efficiency

How long will it take to produce 1 kg of Cl 2 from 20 Lit of 20% by weight NaCl aqueous solution by passing 25 A current with 62% current efficiency is passed.

What is anode and cathode used in the commonly used mercury cell ?

What is cathodic reaction occurring in the commonly used mercury cell ?

What is the reducing agent in the cell?

Name the figure given above.

What is I, II and electrolyte used in the above figure?

Which cell will measure standard electrode potential of copper electrode?

Which of the following statements is/are true for the above figure?

Which of the following statements is not correct about an inert electrode in a cell?

The difference between the electrode potentials of two electrodes when no current is drawn through the cell is called..…..

Electrode potential for Mg electrode varies according to the equation E Mg 2 + / Mg = E Mg 2 + / Mg θ − 0 .059 2 log ⁡ 1 Mg 2 + .The graph of E Mg 2 + / Mg v S log ⁡ Mg 2 + is

Find out in which option the order of reducing power is correct? E Cr 2 O 7 – 2 | Cr + 3 ∘ = 1 . 33 V ; E Cl 2 | Cl ∘ = 1 . 36 V E MnO 4 – | Mn + 2 ∘ = 1 . 51 V ; E Cr + 3 | Cr ∘ = – 0 . 74 V

The cell constant of a conductivity cell………

Λ m NH 4 OH ∘ is equal to ………

Which of the following statements about solution of electrolytes is not correct?

The positive value of the standard electrode potential of Cu 2+ /Cu indicates that

In the electrolysis of aqueous sodium chloride solution which of the half-cell reaction will occur at anode?

The quantity of charge required to obtain one mole of aluminium from Al 2 O 3 is

Conductivity k, is equal to…

Conductivity of an electrolytic solution depends on

What will happen during the electrolysis of aqueous solution of CuSO 4 by using platinum electrodes?

What will happen during the electrolysis of aqueous solution of CuSO 4 in the presence of copper electrodes?

Statement 1: Cu is less reactive than hydrogen. Statement 2: E Cu 2 + / Cu o is negative.

Statement 1: Conductivity of all electrolytes decreases on dilution. Statement 2: On dilution number of ions per unit volume decreases.

Statement 1: E Ag + / Ag increases with increase in concentration of Ag + ions. Statement 2: E Ag + / Ag has a positive value.

Statement 1: Electrolysis of NaCl solution gives chlorine at anode instead of O 2 . Statement 2: Formation of oxygen at anode requires over voltage.

Match the terms given in Column I with the units given in Column II. Column I Column II A. Λ m 1. S cm -1 B. E cell 2. m -1 C. K 3. S cm 2 mol -1 D. G * 4. V

Match the items of Column I and Column II. Column I Column II A. K 1. I × t B. Λ m 2. Λ m / Λ m ∘ C. α 3. κ C D. Q 4. G ∗ R

Match the items of Column I and Column II Column I Column II A. Lead storage battery 1. Maximum efficiency B. Mercury cell 2. Prevented by galvanisation C. Fuel cell 3. Gives steady potential D. Rusting 4. Pb is anode, PbO 2 is cathode

The equivalent conductance of NaCl at concentration C and at infinite dilution are λ C and λ ∞ respectively The correct relationship between λ C and λ ∞ is given as (where, the constant B is positive)

Given below are the half-cell reactions, Mn 2 + + 2 e − ⟶ Mn ; E ∘ = − 1 .18 eV 2 Mn 3 + + e − ⟶ Mn 2 + ; E ∘ = + 1 .51 eV The E ∘ for 3 Mn 2 + ⟶ Mn + 2 Mn 3 + will be

The standard reduction potential for Zn 2 + / Zn , Ni 2 + / Ni and Fe 2 + / Fe are − 0 .76 , − 0 .23 and -0.44 V respectively. The reaction X + Y 2 + ⟶ X 2 + + Y will be spontaneous if

Which of the following half-reaction belongs to a secondary cell ?

Correct decreasing order of equivalent conductivity in aqueous solution at same temperature is

The molar conductance of M 20 solution of weak monoacidic base is 2 .0 S cm 2 mole -1 and at infinite dilution is 200 S cm 2 mole -1 . [H + ] concentration is

Standard reduction potentials E F 2 / F – 0 = 2 . 85 V ; E Cl 2 / Cl – 0 = 1 . 36 V ; E Br 2 / Br – 0 = 1 . 06 V ; E I 2 / I – 0 = 0 . 53 V .Strongest and weakest reducing agents are respectively

Predict the products of electrolysis of the following. An aqueous solution of AgNO 3 with silver electrodes.

In the given reaction, Copper metal, Cu(s) is oxidised to Cu 2 + (aq), while Ag + (aq) is reduced to silver metal, Ag (s), then the equilibrium greatly lies in favour of

Mg ( s ) + 2 Ag + ( 0 . 0001 M ) Mg 2 + ( 0 . 1 M ) + 2 Ag ( s ) The E° for the reaction is 3. 17 V. What is the value of Ε cell for the above reaction ?

The equivalent conductance of two strong electrolytes at infinite dilution in H2O (where ions move freely through a solution) at 25°C are given below λCH 3 COONa = 91 .0.5 Scm 2 / equiv λHCl = 426 .2 Scm 2 / equiv What additional information/quantity one needs to calculate of an aqueous solution of acetic acid?

If the hydrogen electrode is dipped in a solution of pH = 2 at 25° C, then the reduction potential of the electrode would be

The equilibrium constant of the reaction is Cu ( s ) + 2 Ag + ( aq ) Cu 2 + ( aq ) + 2 Ag ( s ) , (Given : E cell 0 = 0 .46 V

The electricity required in coulombs for the oxidation of 0.1 mol of FeO to Fe 2 O 3 is

During electrolysis of molten sodium chloride, time required to produce 0.20 mole of chlorine gas using a current of 6 amperes is

The standard oxidation potential E 0 for the half cell reaction are Fe Fe 2 + + 2 e − ;      E ∘ = + 0 .41 V Cu Cu 2 + + 2 e − ;      E ∘ = − 0 .34 V EMF of the cell reaction is Fe ( s ) + Cu 2 + ( aq ) Fe 2 + ( aq ) + Cu ( s )

The resistance of 0.1 M solution of electrolyte was found to be 200 ohm at 298 K using a conductivity cell of cell constant 0.66 cm -1 . The molar conductance of this solution is

On decreasing the concentration, the conductivity

For hydrogen concentration cell, which is always true?

Equivalent conductivity of Al 2 (SO 4 ) 3 is related to its molar conductivity by the expression of

Pressure of H 2 required to make the potential of hydrogen-electrode zero in pure water at 298 K is:

Electrolysis of aq. K 2 SO 4 using inert electrodes is carried out by passing 9650 coulombs. Weight of the substance obtained at cathode is

Electrolysis of aq. K 2 SO 4 using inert electrodes is carried out by passing 19300 coulombs. Weight of the substance obtained at anode is

Electrolysis of aq. K 2 SO 4 using inert electrodes is carried out by passing 100 amperes for 965 seconds. Volume of the substance obtained at cathode(at STP) is

Electrolysis of aq. K 2 SO 4 using inert electrodes is carried out by passing 100 amperes for 965 seconds. Volume of the substance obtained at cathode(at STP) is

Molar conductance of 0.2 M strong electrolyte AB is 180 mho cm 2 mole – 1 . Specific conductivity of the solution at the same temperature would be——- mho m -1

Molar conductance of decimolar strong electrolyte AB is 360 mho cm 2 mole – 1 . Specific conductivity of the solution at the same temperature would be——- mho m -1

Molar conductance of 2 M strong electrolyte AB is ‘ X ‘ mho cm 2 mole – 1 . Specific conductivity of the solution at the same temperature is 0.09 mho cm -1 . Value of ‘X’ is

Cell notation of a galvanic cell is represented as Ni ( s ) / Ni + 2 ( M 1 ) / / Cl – ( M 2 ) / / 1 2 Cl 2 ( 1 atm ) , Pt ( s ) . Emf of the cell is minimum when the values of M 1 and M 2 are

Cost of Electricity to deposit 12 grams of Magnesium is Rs 600. Cost of Electricity to deposit 10 grams of calcium will be

Reduction potential of Chlorine electrode in contact with 0.01 M KCl solution is ( E Pt , 1 2 Cl 2 / Cl – 0 = + 1 . 36 V )

During the discharge of lead storage battery for 0.5 F of electricity to be generated, the number of moles of H 2 SO 4 consumed is

During the discharge of lead storage battery for 0.25 F of electricity to be generated, the number of moles of H 2 SO 4 consumed is

Oxidation potential of hydrogen electrode is maximum when it is in contact with a solution of

Redution potential of hydrogen electrode is maximum when it is in contact with a solution of

Reduction potential of Silver electrode in contact with 0.1M AgNO 3 solution is ( E Ag + / Ag 0 = + 0 . 8 M )

How many electrons are there in one coulomb of electricity?

The electric charge required for electrode deposition of one gram-equivalent of a substance is :

How many minutes are required to deliver 3.21 x 10 6 coulombs using a current of 500 A used in the commercial production of chlorine?

Electrolysis can be used to determine atomic masses. A current of 0.550 A deposits 0.55 g of a certain metal in 100 minutes. calculate the atomic mass of the metal if eq. mass =mol. mass/3

How many minutes will it take to plate out 52 g of Cr from a Cr 2 (SO 4 ) 3 solution using a current of 9.65 A? (Atomic weight : Cr : 52.0)

Calculate the current (in mA) required to deposit 0.195 g of platinum metal in 5.0 hours from a solution of PtCl 6 2- : (Atomic weight : Pt = 195)

How many Faradays are required to reduce 0.25 g of Nb (V) to the metal? (Atomic weight : Nb = 93g)

One gm metal M 3+ was discharged by the passage of 1.81 x 10 23 electrons. what is the atomic weight of metal?

The electrolytic decomposition of dilute sulphuric acid with platinum electrode, cathodic reaction is :

When an aqueous solution of H 2 SO 4 is electrolysed, the product at anode is :

If Pt is used as cathode in the electrolysis of aqueous NaCl solution, the ion produced at cathode is :

A dilute aqueous solution of CuSO 4 is electrolyzed using platinum electrodes. The products at the anode and cathode are :

Passage of a current for 548 seconds through a silver coulometer results in the deposition of 0.746 g of silver. What is the current (jn A)?

What products are formed during the electolysis of concentrated aqueous solution of sodium chloride? (I) Cl 2 (g) at anode (II) NaOH as electrolyte (III) H 2 (g) at cathode

Beryllium occurs naturally in the form of beryl. The metal is produced from its ore by electrolysis after the ore has been converted to the oxide and then to the chloride. How many grams of Be(s) is deposited from a BeCl 2 solution by a current of 5.0 A that flows for 1.0 h? (Atomic weight : Be = 9)

Which of the following aqueous solution produces metal after electrolysis ?

Which one of the following metals can not be obtained on electrolysis of aqueous solution of its salts ?

The element indium is to be obtained by electrolysis of a molten halide of the element. Passage of a current of 3.20 A for a period of 40.0 min results in formation of 3.05 g of In. What is the oxidation state of indium in the halide melt

Use of electrolysis is in :

A current of 9.65 ampere is passed through 0.2 M,500 mL aqueous solution of CuSO 4 using Cu-electrode for 300 sec. than calculate [Cu 2+ ] concentration in the resulting solution. If volume of solution remains constant:

How much time is required for complete decomposition of two moles of water using 4 ampere?

If electrolysis of CuSO 4 solution is carried out with 100g impure Cu as anode of 90% purity and pure Cu of mass 1009 as cathode by passing 2 amp. current for 9650 sec. Then mass of cathode and anode will be: (At. mass of Cu = 63)

The function of a salt bridge is to :

The Nernst equation E = E o -RT /nF lnQ indicates that the Q will be equal to equilibrium constant K c when

Select the correct cell reaction of the cell Pt ( s ) Cl 2 ( g ) Cl − ( aq ) ∥ Ag + ( aq ) ∣ Ag ( s ) :

Select the correct cell reaction of the cell Ag ( s ) | | Ag + ( aq ) ∥ Cu 2 + ( aq ) ∣ Cu ( s ) :

Zn can displace :

The element which can displace three other halogens from their compound is :

Which of the following is displaced by Fe?

What will be the emf for the given cell? Pt H 2 g , P 1 H + ( aq ) H 2 g , P 2 Pt

Thermodynamic efficiency of a cell is given by :

When a lead storage battery is charged it acts as :

Which of the following statement is false for fuel cells?

The metal that forms a self-protecting film of oxide to prevent corrosion is :

Rusting of iron is catalyzed by which of the following ?

In electrochemical corrosion of metals, the metal undergoing corrosion :

Which of the following is a highly corrosive salt ?

Rusting of iron is:

Electrolytic conduction is due to the movement of :

When an acid cell is charged, then :

Molten sodium chloride conducts electricity due to the presence of :

The relation among conductance (G), specific conductance (r) and cell constant (l/A) is :

Molar conductivity of a solution of an electrolyte AB 3 is 150 scm 2 mol -1 . If it ionises as AB 3 ⟶ A 3 + + 3 B − , its equivalent conductivity will be :

The resistance of 0.1 N solution of formic acid is 200 ohm and cell constant is 2.0 cm -1 . The equivalent conductivity (in Scm 2 eq -1 ) of 0.1 N formic acid is:

Equivalent conductance can be expressed in terms of specific conductance (k) and concentration (N) in gram equivalent dm -3 as :

The ionic conductivity of Ba 2+ and Cl – at infinite dilution are 127 and 76 ohm -1 cm 2 eq -1 , respectively. The equivalent conductivity of BaCl 2 at infinity dilution (in ohm -1 cm 2 eq -1 ) would be :

Equivalent conductivity of Fe 2 (SO 4 ), is related to molar conductivity by the expression :

Resistance of 0.1 M KCl solution in a conductance cell is 300 ohm and conductivity is 0.013 Scm -1 . The value of cell constant is :

The limiting equivalent conductivity of NaCl, KCI and KBr are 126.s, 150.0 and151.5 scm 2 eq -1 , respectively. The limiting equivalent ionic conductance for Br – is 78 S cm 2 eq -1 . The limiting equivalent ionic conductance for Na + ions would be :

Λ AgCl ∞ can be obtained :

The increase in equivalent conductance of a weak electrolyte with dilution is due to :

Strong electrolytes are those which :

The electric conduction of a salt solution in water depends on the :

The conductivity of a strong electrolyte :

HNO 3 (aq) is titrated with NaOH(aq) conducto metrically, graphical representation of the titration as :

Conductometric titration curve of a equimolar mixture of a HCI and HCN with NaOH (ag) is :

A graph was plotted between molar conductivity of various electrolytes (NaCl, HCI and NH 4 OH) and C (in mol L -1 ). Correct setting :

Which of the following plots will obtained for a conductometric titration of strong acid against a weak base?