JEE Main
Chemistry
Electrochemistry
Previous Years Questions

## Numerical

$$1 \times 10^{-5} ~\mathrm{M} ~\mathrm{AgNO}_{3}$$ is added to $$1 \mathrm{~L}$$ of saturated solution of $$\mathrm{AgBr}$$. The conductivity of this...
At what pH, given half cell $$\mathrm{MnO_{4}^{-}(0.1~M)~|~Mn^{2+}(0.001~M)}$$ will have electrode potential of 1.282 V? ___________ (Nearest Integer)...
The resistivity of a $0.8 \mathrm{M}$ solution of an electrolyte is $5 \times 10^{-3} \Omega~ \mathrm{cm}$. Its molar conductivity is _________ $\tim... The logarithm of equilibrium constant for the reaction $$\mathrm{Pd}^{2+}+4 \mathrm{Cl}^{-} \rightleftharpoons \mathrm{PdCl}_{4}^{2-}$$ is ___________... The electrode potential of the following half cell at$298 \mathrm{~K}\mathrm{X}\left|\mathrm{X}^{2+}(0.001 \mathrm{M}) \| \mathrm{Y}^{2+}(0.01 \m...
Consider the cell $$\mathrm{Pt}_{(\mathrm{s})}\left|\mathrm{H}_{2}(\mathrm{~g}, 1 \mathrm{~atm})\right| \mathrm{H}^{+}(\mathrm{aq}, 1 \mathrm{M})|| \m... The equilibrium constant for the reaction$$\mathrm{Zn(s)+Sn^{2+}(aq)}\rightleftharpoons\mathrm{Zn^{2+}(aq)+Sn(s)}$$is$$1\times10^{20}$$a... Following figure shows dependence of molar conductance of two electrolytes on concentration.$$\Lambda \mathop m\limits^o $$is the limiting molar con...$$Pt(s)|{H_2}(g)(1\,bar)|{H^ + }(aq)(1\,M)||{M^{3 + }}(aq),{M^ + }(aq)|Pt(s)$$The$$\mathrm{E_{cell}}$$for the given cell is 0.1115 V at 298 K when ... Consider the cell$$\mathrm{Pt(s)|{H_2}(g)\,(1\,atm)|{H^ + }\,(aq,[{H^ + }] = 1)||F{e^{3 + }}(aq),F{e^{2 + }}(aq)|Pt(s)}$$Given$$\mathrm{E_{F{e^{3 +...
At 298 K, a 1 litre solution containing 10 mmol of $$\mathrm{C{r_2}O_7^{2 - }}$$ and 100 mmol of $$\mathrm{Cr^{3+}}$$ shows a pH of 3.0. Given : $$\ma... For a cell,$$\mathrm{Cu}(\mathrm{s})\left|\mathrm{Cu}^{2+}(0.001 \,\mathrm{M}) \| \mathrm{Ag}^{+}(0.01 \,\mathrm{M})\right| \mathrm{Ag}(\mathrm{s})$$... Resistance of a conductivity cell (cell constant$$129 \mathrm{~m}^{-1}$$) filled with$$74.5 \,\mathrm{ppm}$$solution of$$\mathrm{KCl}$$is$$100 \...
The amount of charge in $$\mathrm{F}$$ (Faraday) required to obtain one mole of iron from $$\mathrm{Fe}_{3} \mathrm{O}_{4}$$ is ___________. (Nearest ...
The spin-only magnetic moment value of M3+ ion (in gaseous state) from the pairs Cr3+ / Cr2+, Mn3+ / Mn2+, Fe3+ / Fe2+ and Co3+ / Co2+ that has negati...
The enthalpy of combustion of propane, graphite and dihydrogen at $$298 \mathrm{~K}$$ are $$-2220.0 \mathrm{~kJ} \mathrm{~mol}^{-1},-393.5 \mathrm{~kJ... The cell potential for$$\mathrm{Zn}\left|\mathrm{Zn}^{2+}(\mathrm{aq})\right|\left|\mathrm{Sn}^{x+}\right| \mathrm{Sn}$$is$$0.801 \mathrm{~V}$$at ... The cell potential for the given cell at 298 K Pt| H2 (g, 1 bar) | H+ (aq) || Cu2+ (aq) | Cu(s) is 0.31 V. The pH of the acidic solution is found to b... A dilute solution of sulphuric acid is electrolysed using a current of 0.10 A for 2 hours to produce hydrogen and oxygen gas. The total volume of gase... For the given reactions Sn2+ + 2e$$-\to$$Sn Sn4+ + 4e$$-\to$$Sn the electrode potentials are ;$$E_{S{n^{2 + }}/Sn}^o = - 0.140$$V and ... The quantity of electricity in Faraday needed to reduce 1 mol of Cr2O$$_7^{2 - }$$to Cr3+ is ____________. For the reaction taking place in the cell : Pt (s)| H2 (g)|H+(aq) || Ag+(aq) |Ag (s) E$$_{cell}^o$$= + 0.5332 V. The value of$$\Delta$$fG$$^\circ$$... The limiting molar conductivities of NaI, NaNO3 and AgNO3 are 12.7, 12.0 and 13.3 mS m2 mol$$-$$1, respectively (all at 25$$^\circ$$C). The limiting m... Cu(s) + Sn2+ (0.001M)$$\to$$Cu2+ (0.01M) + Sn(s) The Gibbs free energy change for the above reaction at 298 K is x$$\times$$10$$-$$1 kJ mol$$-$$1.... A solution of Fe2(SO4)3 is electrolyzed for 'x' min with a current of 1.5 A to deposit 0.3482 g of Fe. The value of x is ___________. [nearest integer... In a cell, the following reactions take place$$\matrix{ {F{e^{2 + }} \to F{e^{3 + }} + {e^ - }} & {E_{F{e^{3 + }}/F{e^{2 + }}}^o = 0.77\,V} \cr ...
The resistance of a conductivity cell containing 0.01 M KCl solution at 298 K is 1750 $$\Omega$$. If the conductivity of 0.01 M KCl solution at 298 K ...
The cell potential for the following cell Pt |H2(g)|H+ (aq)|| Cu2+ (0.01 M)|Cu(s) is 0.576 V at 298 K. The pH of the solution is __________. (Nearest ...
If the conductivity of mercury at 0$$^\circ$$C is 1.07 $$\times$$ 106 S m$$-$$1 and the resistance of a cell containing mercury is 0.243$$\Omega$$, th...
Consider the following cell reaction :$$C{d_{(s)}} + H{g_2}S{O_{4(s)}} + {9 \over 5}{H_2}{O_{(l)}}$$ $$\rightleftharpoons$$ $$CdS{O_4}.{9 \over 5}{H_2... The resistance of a conductivity cell with cell constant 1.14 cm$$-$$1, containing 0.001 M KCl at 298 K is 1500$$\Omega$$. The molar conductivity of ... For the galvanic cell,Zn(s) + Cu2+ (0.02 M)$$\to$$Zn2+ (0.04 M) + Cu(s),Ecell = ______________$$\times$$10$$-$$2 V. (Nearest integer)[Use :$$E_{C...
For the cellCu(s) | Cu2+ (aq) (0.1 M) || Ag+(aq) (0.01 M) | Ag(s)the cell potential E1 = 0.3095 VFor the cellCu(s) | Cu2+ (aq) (0.01 M) || Ag+(aq) (0....
The conductivity of a weak acid HA of concentration 0.001 mol L$$-$$1 is 2.0 $$\times$$ 10$$-$$5 S cm$$-$$1. If $$\Lambda _m^o$$(HA) = 190 S cm2 mol$$... Consider the cell at 25$$^\circ$$CZn | Zn2+ (aq), (1M) || Fe3+ (aq), Fe2+ (aq) | Pt(s)The fraction of total iron present as Fe3+ ion at the cell poten... Assume a cell with the following reaction$$C{u_{(s)}} + 2A{g^ + }(1 \times {10^{ - 3}}M) \to C{u^{2 + }}(0.250M) + 2A{g_{(s)}}E_{cell}^\Theta = 2...
Potassium chlorate is prepared by electrolysis of KCl in basic solution as shown by following equation.6OH$$-$$ + Cl$$-$$ $$\to$$ ClO3$$-$$ + 3H2O + 6...
The molar conductivities at infinite dilution of barium chloride, sulphuric acid and hydrochloric acid are 280, 860 and 426 S cm2 mol$$-$$1 respective...
For the reaction 2Fe3+(aq) + 2I$$-$$(aq) $$\to$$ 2Fe2+(aq) + I2(s) the magnitude of the standard molar free energy change, $$\Delta$$rG$$_m^o$$ = $$... A KCl solution of conductivity 0.14 S m$$-$$1 shows a resistance of 4.19$$\Omega$$in a conductivity cell. If the same cell is filled with an HCl solu... A 5.0 m mol dm$$-$$3 aqueous solution of KCl has a conductance of 0.55 mS when measured in a cell of cell constant 1.3 cm$$-$$1. The molar conductivit... Emf of the following cell at 298K in V is x$$\times$$10$$-$$2.Zn|Zn2+(0.1 M)||Ag+ (0.01 M)|AgThe value of x is _________. (Rounded off to the neares... Consider the following reaction$$MnO_4^ - + 8{H^ + } + 5{e^ - } \to M{n^{ + 2}} + 4{H_2}O,{E^o} = 1.51V$$.The quantity of electricity required in Far... Copper reduces NO$$_3^ - $$into NO and NO2 depending upon the concentration of HNO3 in solution. (Assuming fixed [Cu2+] and PNO = PNO2), the HNO3 con... Electromagnetic radiation of wavelength 663 nm is just sufficient to ionise the atom of metal A. The ionization enegy of metal A in kJ mol$$-$$1 is __... Among the following, number of metal/s which can be used as electrodes in the photoelectric cell is _________. (Integer answer)(A) Li(B) Na(C) Rb(D) C... 1 molal aqueous solution of an electrolyte A2B3 is 60% ionised. The boiling point of the solution at 1 atm is _________ K. (Rounded off to the nearest... The magnitude of the change in oxidising power of the$$MnO_4^ - /M{n^{2 + }}$$couple is x$$\times$$10$$-$$4 V, if the H+ concentration is decrease... Potassium chlorate is prepared by the electrolysis of KCl in basic solution 6OH- + Cl-$$ \to $$ClO3- + 3H2O + 6e- If only 60% of the current is util... The volume, in mL, of 0.02 M K2Cr2O7 solution required to react with 0.288 g of ferrous oxalate in acidic medium is _______. (Molar mass of Fe = 56 g ... An oxidation-reduction reaction in which 3 electrons are transferred has a$$\Delta $$Gº of 17.37 kJ mol–1 at 25 oC. The value of Eo cell (in V) is __... An acidic solution of dichromate is electrolyzed for 8 minutes using 2A current. As per the following equation Cr2O72- + 14H+ + 6e–$$ \to $$2Cr3+ +... The photoelectric current from Na (Work function, w0 = 2.3 eV) is stopped by the output voltage of the cell Pt(s) | H2 (g, 1 Bar) | HCl (aq., pH =1) ... The Gibbs change (in J) for the given reaction at [Cu2+] = [Sn2+] = 1 M and 298K is : Cu(s) + Sn2+(aq.)$$ \to $$Cu2+(aq.) + Sn(s); ($$E_{S{n^{2 + }...
108 g of silver (molar mass 108 g mol–1) is deposited at cathode from AgNO3(aq) solution by a certain quantity of electricity. The volume (in L) of ox...
For an electrochemical cell Sn(s) | Sn2+ (aq,1M)||Pb2+ (aq,1M)|Pb(s) the ratio $${{\left[ {S{n^{2 + }}} \right]} \over {\left[ {P{b^{2 + }}} \right]}}... What would be the electrode potential for the given half cell reaction at pH = 5? ______. 2H2O$$ \to $$O2 + 4H$$ \oplus $$+ 4e– ;$$E_{red}^0$$= 1... For the reaction : A($$l$$)$$ \to $$2B(g)$$\Delta U = 2.1\,kcal,\,\Delta S = 20\,cal\,{K^{ - 1}}$$at 300 K Hence$$\Delta $$G in kcal is... ## MCQ (Single Correct Answer) Which one of the following statements is correct for electrolysis of brine solution? The standard electrode potential$$\mathrm{(M^{3+}/M^{2+})}$$for V, Cr, Mn & Co are$$-$$0.26 V,$$-$$0.41 V, + 1.57 V and + 1.97 V, respectively. Th... Match List - I with List - II. .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-f... Given below are two statements : Statement I : For KI, molar conductivity increases steeply with dilution Statement II : For carbonic acid, molar cond... The molar conductivity of a conductivity cell filled with 10 moles of 20 mL NaCl solution is$${\Lambda _{m1}}$$and that of 20 moles another identica... In which of the following half cells, electrochemical reaction is pH dependent? In 3d series, the metal having the highest M2+/M standard electrode potential is The$${\left( {{{\partial E} \over {\partial T}}} \right)_P}$$of different types of half cells are as follows: .tg {border-collapse:collapse;border... The correct order of reduction potentials of the following pairs is A. Cl2/Cl$$-$$B. I2/I$$-$$C. Ag+/Ag D. Na+/Na E. Li+/Li Choose the correct answe... Match List - I with List - II List - I(Parmeter) List - II(Unit) (a) Cell constant (i)$$S\,c{m^2}mo{l^{...
Given below are two statements :Statement I : The limiting molar conductivity of KCl (strong electrolyte) is higher compared to that of CH3COOH (weak ...
Given below are two statements :Statement I : The Eo value for Ce4+ / Ce3+ is + 1.74 V.Statement II : Ce is more stable in Ce4+ state than Ce3+ state....
The electrode potential of M2+/M of 3d-series elements shows positive value for :
For the given cell : Cu(s) | Cu2+(C1M) || Cu2+(C2M) | Cu(s) change in Gibbs energy ($$\Delta$$G) is negative, if...
The variation of molar conductivity with concentration of an electrolyte (X) in aqueous solution is shown in the given figure. The electrolyte X is :...
250 mL of a waste solution obtained from the workshop of a goldsmith contains 0.1 M AgNO3 and 0.1 M AuCl. The solution was electrolyzed at 2V by passi...
$$E_{C{u^{2 + }}|Cu}^0$$ = +0.34 V $$E_{Z{n^{2 + }}|Zn}^0$$ = -0.76 V Identify the incorrect statement from the option below for the above cell :...
The equation that is incorrect is :
Given that the standard potentials (Eo) of Cu2+/Cu and Cu+/Cu are 0.34 V and 0.522 V respectively, the Eo of Cu2+/Cu+ ...
The decreasing order of electrical conductivity of the following aqueous solutions is : 0.1 M Formic acid (A), 0.1 M Acetic acid (B), 0.1 M Benzoic ac...
Given CO3+ + e– $$\to$$ CO2+ ; Eo = + 1.81 V Pb4+ + 2e– $$\to$$ Pb2+ ; Eo = + 1.67 V Ce4+ + e– $$\to$$ Ce3+ ; Eo = + 1.61 V Bi3+ + 3e– $$\to... A solution of Ni(NO3)2 is electrolysed between platinum electrodes using 0.1 Faraday electricity. How many mole of Ni will be deposited at the cathode... The standard Gibbs energy for the given cell reaction in kJ mol–1 at 298 K is : Zn(s) + Cu2+ (aq)$$ \to $$Zn2+ (aq) + Cu (s), E° = 2 V at 298 K (Far... Calculate the standard cell potential in (V) of the cell in which following reaction takes place : Fe2+(aq) + Ag+(aq)$$ \to $$Fe3+(aq) + Ag (s) Give... Given that$${E^\Theta }_{{O_2}/{H_2}O} = 1.23\,V$$;$${E^\Theta }_{{S_2}O_8^{2 - }/SO_4^{2 - }} = 2.05\,V{E^\Theta }_{B{r_2}/B{r^ - }} = 1.09\,...
$$\wedge _m^ \circ$$ for NaCl, HCl and NaA are 126.4, 425.9 and 100.5 S cm2 mol–1, respectively. If the conductivity of 0.001 M HA is- 5 $$\times... Given (i) C (graphite) + O2(g)$$ \to $$CO2(g);$$\Delta $$rH$$^\Theta $$= x kJ mol$$-$$1 (ii) C(graphite) +$${1 \over 2}$$O... The standard electrode potential$${E^o }$$and its temperature coefficient$$\left( {{{d{E^o }} \over {dT}}} \right)$$for a cell are 2V and$$-$$5 ... For the cell Zn(s) |Zn2+ (aq)| |Mx+ (aq)| M(s), different half cells and their standard electrode potentials are given below : .tg {border-collapse... In the cell Pt$$\left| {\left( s \right)} \right|$$H2(g, 1 bar)$$\left| {HCl\left( {aq} \right)} \right|$$AgCl$$\left| {\left( s \right)} \right|$$A... Consider the following reduction processes : Zn2+ + 2e–$$ \to $$Zn(s) ; Eo = – 0.76 V Ca2+ + 2e–$$ \to $$Ca(s); Eo = –2.87 V Mg2+ + 2e–$$ \to $$... The anodic half-cell of lead-acid battery is recharged using electricity of 0.05 Faraday. The amount of PbSO4 electrolyzed in g during the process is ... When 9.65 ampere current was passed for 1.0 hour into nitrobenzene in acidic medium, the amount of p-aminophenol produced is : How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn 27.66 g of ... When an electric currents passed through acidified water, 112 mL of hydrogen gas at N.T.P. was collected at the cathode in 965 seconds. The current pa... To find the standard potential of M3+/M electrode,the following cell is constituted : Pt/M/M3+(0.001 mol L−1 )/Ag+(0.01 mol L−1 )/Ag The emf of the c... What is the standard reduction potential (Eo) for Fe3+$$ \to $$Fe ? Given that : Fe2+ + 2e$$- \to $$Fe;$$E_{F{e^{2 + }}/Fe}^o$$=$$-$$0.47 ... Consider the following standard electrode potentials (Eo in volts) in aqueous solution : .tg {border-collapse:collapse;border-spacing:0;} .tg td{fon... Given$$E_{C{l_2}/C{l^ - }}^o$$= 1.36 V,$$E_{C{r^{3 + }}/Cr}^o$$= - 0.74 V$$E_{C{r_2}{O_7}^{2 - }/C{r^{3 + }}}^o$$= 1.33 V,$$E_{Mn{O_4}^ - /Mn ^...
Oxidation of succinate ion produces ethylene and carbon dioxide gases. On passing 0.2 Faraday electricity through an aqueous solution of potassium suc...
Identify the correct statement :
What will occur if a block of copper metal is dropped into a beaker containing a solution of 1M ZnSO4 ?
Galvanization is applying a coating of:
Two Faraday of electricity is passed through a solution of CuSO4. The mass of copper deposited at the cathode is: (at. mass of Cu = 63.5 amu)...
Resistance of 0.2 M solution of an electrolyte is 50 $$\Omega$$. The specific conductance of the solution is 1.4 S m-1. The resistance of 0.5 M soluti...
Given below are the half-cell reactions: Mn2+ + 2e- $$\to$$ Mn; Eo = -1.18 V 2(Mn3+ + e- $$\to$$ Mn2+); Eo = +1.51 V The Eo for 3Mn2+ $$\to$$ Mn + 2Mn...
The equivalent conductance of NaCl at concentration C and at infinite dilution are $${\lambda _C}$$ and $${\lambda _\infty }$$, respectively. The cor...
Given $$E_{C{r^{2 + }}/Cr}^o$$ = -0.74 V; $$E_{MnO_4^ - /M{n^{2 + }}}^o$$ = 1.51 V $$E_{C{r_2}O_7^{2 - }/C{r^{3 + }}}^o$$ = 1.33 V; $$E_{Cl/C{l^ - }}^... The standard reduction potentials for Zn2+/ Zn, Ni2+/ Ni, and Fe2+/ Fe are –0.76, –0.23 and –0.44 V respectively. The reaction X + Y2+$$\to$$X2+ + Y... The reduction potential of hydrogen half cell will be negative if : The correct order of$$E_{{M^{2 + }}/M}^o$$values with negative sign for the four successive elements Cr, Mn, Fe and Co is The Gibbs energy for the decomposition of Al2O3 at 500oC is as follows :$${2 \over 3}A{l_2}{O_3}\to{4 \over 3}Al + {O_2}$$,$${\Delta _r}G$... Given : $$E_{F{e^{3 + }}/Fe}^o$$ = -0.036V; $$E_{F{e^{2 + }}/Fe}^o$$ = -0.439 V The value of standard electrode potential for the change, Fe3+ (aq) ... In a fuel cell methanol is used as fuel and oxygen gas is used as an oxidizer. The reaction is CH3OH(l) + 3/2O2 $$\to$$ CO2 (g) + 2H2O (l) At 298K s... Given $$E_{C{r^{3 + }}/Cr}^o$$ = -0.72 V; $$E_{Fe^{2+}/Fe}^o$$ = -0.42V, The potential for the cell Cr | Cr3+ (0.1M) || Fe2+ (0.01 M) | Fe is... The equivalent conductances of two strong electrolytes at infinite dilution in H2O (where ions move freely through a solution) at 25oC are given below... The cell, Zn | Zn2+ (1M) || Cu2+ (1M) | Cu($$E_{cell}^o$$ = 1.10V) was allowed to be completely discharged at 298 K. The relative concentration of Zn... The molar conductivities $$\wedge _{NaOAc}^o$$ and $$\wedge _{HCl}^o$$ and at infinite dilution in water at 25oC are 91.0 and 426.2 Scm2/mol respec... Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0.1 M is 100$$\Omega$$. The conductivity of this solution... For a spontaneous reaction the ∆G , equilibrium constant (K) and $$E_{cell}^o$$ will be respectively Aluminium oxide may be electrolysed at 1000oC to furnish aluminium metal (Atomic mass = 27 amu; 1 Faraday = 96,500 Coulombs). The cathode reaction is ... The highest electrical conductivity of the following aqueous solutions is of .tg {border-collapse:collapse;border-spacing:0;} .tg td{font-family:Arial, sans-serif;font-size:14px;padding:10px 5px;border-style:solid;border-wid... In a hydrogen – oxygen fuel cell, combustion of hydrogen occurs to Consider the following Eo values $$E_{F{e^{3 + }}/F{e^{2 + }}}^o$$ = 0.77 V; $$E_{S{n^{2 + }}/S{n}}^o$$ = -0.14 V Under standard conditions the poten... The standard e.m.f of a cell, involving one electron change is found to be 0.591 V at 25oC. The equilibrium constant of the reaction is (F = 96,500 C ... The limiting molar conductivities Λ° for NaCl, KBr and KCl are 126, 152 and 150 S cm2 mol-1 respectively. The Λ° for NaBr is In a cell that utilises the reaction Zn(s) + 2H+ (aq) $$\to$$ Zn2+(aq) + H2(g) addition of H2SO4 to cathode compartment, will ... The $$E_{{M^{3 + }}/{M^{2 + }}}^o$$ values for Cr, Mn, Fe and Co are – 0.41, +1.57, + 0.77 and +1.97 V respectively. For which one of these metals th... Standard reduction electrode potentials of three metals A,B&C are respectively +0.5 V, -3.0 V & -1.2 V. The reducing, powers of these metals a... 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 25oC. The equilibrium constant of the r... When during electrolysis of a solution of AgNO3 9650 coulombs of charge pass through the electroplating bath, the mass of silver deposited on the cath... For the redox reaction Zn(s) + Cu2+(0.1 M) $$\to$$ Zn2+(1M) + Cu(s) taking place in a cell, $$E_{cell}^o$$ is 1.10 volt. Ecell for the cell will be (... Several blocks of magnesium are fixed to the bottom of a ship to Conductivity (unit Siemen’s S) is directly proportional to area of the vessel and the concentration of the solution in it and is inversely proportiona... For the following cell with hydrogen electrodes at two different pressure p1 and p2. What will be the emf for the given cell$\$\eqalign{ & Pt({...
EMF of a cell in terms of reduction potential of its left and right electrodes is
Which of the following reaction is possible at anode?
When the sample of copper with zinc impurity is to be purified by electrolysis, the appropriate electrodes are
EXAM MAP
Joint Entrance Examination