JEE Main & Advanced Chemistry Electrochemistry / विद्युत् रसायन Sample Paper

done Topic Test - Electrochemistry Total Questions - 35    [Download]

• question_answer1)
  Molar conductance of a 1.5 M solution of an electrolyte is found to be \[138.9\text{ }S\text{ }c{{m}^{2}}\]. The specific conductance of this solution is
  A)
  \[0.208\text{ S}\,\text{c}{{\text{m}}^{-1}}\]
  done clear
  B)
  \[0.102\text{ S}\,\text{c}{{\text{m}}^{-1}}\]
  done clear
  C)
  \[0.320\text{ S}\,\text{c}{{\text{m}}^{-1}}\]
  done clear
  D)
  \[0.152\text{ S}\,\text{c}{{\text{m}}^{-1}}\]
  done clear
  View Answer play_arrow

• question_answer2)

  Given the following half reactions:

  \[{{A}^{2+}}+{{e}^{-}}\to {{A}^{+}},{{E}^{o}}=+1.70V\]

  \[{{B}^{2+}}+2{{e}^{-}}\to {{B}^{+}},{{E}^{o}}=+0.60V\]

  \[{{C}^{3+}}+{{e}^{-}}\to {{C}^{2+}},{{E}^{o}}=+0.90V\]

  The only reaction that could be used in titration would be

  A)
  \[{{A}^{+}}\] with \[{{B}^{4+}}\]
  done clear
  B)
  \[{{A}^{+}}\] with \[{{C}^{3+}}\]
  done clear
  C)
  \[{{A}^{2+}}\] with \[{{C}^{2+}}\]
  done clear
  D)
  \[{{C}^{2+}}\] with \[{{B}^{4+}}\]
  done clear
  View Answer play_arrow

• question_answer3)

  Emf of the cell

  \[Ni|N{{i}^{2+}}(0.1\,M)||A{{u}^{3+}}\,(1.0\,M)|\,Au\] will be

  \[(E_{Ni/N{{i}^{2+}}}^{{}^\circ }=0.25,\,E_{Au/A{{u}^{3+}}}^{{}^\circ }=1.5\,V)\]

  A)
  1.75 V
  done clear
  B)
  \[+\]1.7795 V
  done clear
  C)
  \[+\]0.7795 V
  done clear
  D)
  \[-\]1.7795 V
  done clear
  View Answer play_arrow

• question_answer4)
  \[Zn|Z{{n}^{+2}}({{C}_{1}})||Z{{n}^{+2}}({{C}_{2}})|Zn\] For this cell \[\Delta G\] is negative if
  A)
  \[{{C}_{1}}={{C}_{2}}\]
  done clear
  B)
  \[{{C}_{1}}>{{C}_{2}}\]
  done clear
  C)
  \[{{C}_{2}}>{{C}_{1}}\]
  done clear
  D)
  Both [a] and [c] are correct
  done clear
  View Answer play_arrow

• question_answer5)
  Equivalent conductivity of \[BaC{{l}_{2}},{{H}_{2}}S{{O}_{4}}\] and HCl are \[{{y}_{1}},{{y}_{2}}\] and \[{{y}_{3}}S\,c{{m}^{-1}}e{{q}^{-1}}\] at infinite dilution. If conductivity of saturated \[BaS{{O}_{4}}\] solution is \[y\,S\,c{{m}^{-1}},\] then find \[{{K}_{sp}}\] of \[BaS{{O}_{4}}\].
  A)
  \[\frac{{{y}^{2}}}{{{({{y}_{1}}+{{y}_{2}}-{{y}_{3}})}^{2}}}\]
  done clear
  B)
  \[\frac{2.5{{y}^{-2}}}{{{({{y}_{1}}+{{y}_{2}}-{{y}_{3}})}^{2}}}\]
  done clear
  C)
  \[\frac{500}{{{y}_{1}}+{{y}_{2}}-{{y}_{3}}}\]          
  done clear
  D)
  \[\frac{2.5\times {{10}^{5}}{{y}^{2}}}{{{({{y}_{1}}+{{y}_{2}}-{{y}_{3}})}^{2}}}\]
  done clear
  View Answer play_arrow

• question_answer6)
  A current of 2.0 A when passed for 5 hours through a molten metal salt deposits 22.2 g of metal of atomic weight 177. The oxidation state of the metal in the metal salt is
  A)
  + 1
  done clear
  B)
  + 2
  done clear
  C)
  + 3
  done clear
  D)
  + 4
  done clear
  View Answer play_arrow

• question_answer7)
  A current of 0.250 A is passed through 400 mL of a 2, 0 M solution of NaCl for 35 minutes. What will be the pH of the solution after the current is turned off?
  A)
  12.98 
  done clear
  B)
  12.13    
  done clear
  C)
  10.48
  done clear
  D)
  9.24
  done clear
  View Answer play_arrow

• question_answer8)
  Acidulated water is electrolysed by 1 A current for 16 min and 5s using inert electrodes, The volume of gases liberated at STP will be
  A)
  22.4 mL
  done clear
  B)
  112 mL
  done clear
  C)
  168 mL
  done clear
  D)
  336 mL
  done clear
  View Answer play_arrow

• question_answer9)
  Equivalent conductance of saturated \[BaS{{O}_{4}}\] is \[400\,{{\Omega }^{-1}}\,c{{m}^{2}}eq{{u}^{-1}}\] and specific conductance is\[8\times {{10}^{-5}}\,{{\Omega }^{-1}}\,c{{m}^{-1}}\]. Hence, \[{{K}_{sp}}\] of \[BaS{{O}_{4}}\] is
  A)
  \[4\times {{10}^{-8}}{{M}^{2}}\]
  done clear
  B)
  \[1\times {{10}^{-8}}{{M}^{2}}\]
  done clear
  C)
  \[2\times {{10}^{-4}}{{M}^{2}}\]
  done clear
  D)
  \[1\times {{10}^{-4}}{{M}^{2}}\]
  done clear
  View Answer play_arrow

• question_answer10)
  The reduction potential of hydrogen half-cell will be negative if
  A)
  \[p({{H}_{2}})=2\,atm\,and\,[{{H}^{+}}]=2.0M\]
  done clear
  B)
  \[p({{H}_{2}})=1\,atm\,and\,[{{H}^{+}}]=2.0M\]
  done clear
  C)
  \[p({{H}_{2}})=1\,atm\,and\,[{{H}^{+}}]=1.0M\]
  done clear
  D)
  \[p({{H}_{2}})=2\,atm\,and\,[{{H}^{+}}]=1.0M\]
  done clear
  View Answer play_arrow

• question_answer11)

  EMF of which of the following cells at 298 K is highest?

  Given,   \[E_{\left( M{{g}^{2+}}/mg \right)}^{0}=-2.37V;\]

  \[E_{\left( C{{u}^{2}}/Cu \right)}^{0}=+2.34V;\]

  \[E_{\left( F{{e}^{2+}}/Fe \right)}^{0}=-0.44V;\]

  \[E_{\left( S{{n}^{2+}}/Sn \right)}^{0}=-0.14V;\]

  \[E_{\left( \frac{1}{2}B{{r}_{2}}/B{{r}^{-}} \right)}^{0}=+1.08V;\]

  A)
  \[Mg(s)|M{{g}^{2+}}(0.001M)|\]\[|C{{u}^{2+}}(0.0001M)|Cu(s)\]
  done clear
  B)
  \[Fe(s)|F{{e}^{2+}}(0.001M)|\]\[|{{H}^{+}}(1M)|{{H}_{2}}(g)(1bar)|Pt(s)\]
  done clear
  C)
  \[Sn(s)S{{n}^{2+}}(0.050M)|\]\[|{{H}^{+}}(0.020M)|{{H}_{2}}(g)(1bar)|Pt(s)\]
  done clear
  D)
  \[Pt(s)|B{{r}_{2}}(l)|B{{r}^{+}}(0.010M)|\]\[|{{H}^{+}}(0.030M)|{{H}_{2}}(g)(1bar)|Pt(s)\]
  done clear
  View Answer play_arrow

• question_answer12)
  On electrolyzing the molten chloride of metal \[725\text{ }ml\] of \[C{{l}_{2}}\] liberated at \[25{}^\circ C\] and 740 mm Hg pressure at anode for every one gm of metal deposite at cathode. The formula of metal chloride is (GAM of metal \[=52.01\])                        
  A)
  \[MCI\]
  done clear
  B)
   \[MC{{I}_{2}}\]
  done clear
  C)
  \[MC{{I}_{3}}\]
  done clear
  D)
  \[MC{{I}_{4}}\]
  done clear
  View Answer play_arrow

• question_answer13)
  The standard electrode potential for the following reaction is + 1.33 V. What is the potential at pH = 2? \[C{{r}_{2}}O_{7}^{2-}(aq1M)+14{{H}^{\oplus }}(aq)+6{{e}^{-}}\]\[\xrightarrow{\,}\,2C{{r}^{3+}}(aq1M)+7{{H}_{2}}O(l)\]
  A)
  +1.82 V
  done clear
  B)
  +1.99 V
  done clear
  C)
  +1.608 V
  done clear
  D)
  +1.054 V
  done clear
  View Answer play_arrow

• question_answer14)
  Molar conductance's of \[BaC{{l}_{2}},{{H}_{2}}S{{O}_{4}}\] and HCl at infinite dilutions are \[{{x}_{1}},{{x}_{2}}\] and \[{{x}_{3}}\] respectively. Equivalent conductance of \[BaS{{O}_{4}}\] at infinite dilution will be:
  A)
  \[({{x}_{1}}+{{x}_{2}}-{{x}_{3}})/2\]
  done clear
  B)
  \[{{x}_{1}}+{{x}_{2}}-2{{x}_{3}}\]
  done clear
  C)
  \[({{x}_{1}}-{{x}_{2}}-{{x}_{3}})/2\]
  done clear
  D)
  \[({{x}_{1}}+{{x}_{2}}-2{{x}_{3}})/2\]
  done clear
  View Answer play_arrow

• question_answer15)
  Galvanic cell involves
  A)
  conversion of thermal energy (Heating) into electrical energy
  done clear
  B)
  conversion of electrical energy into chemical energy
  done clear
  C)
  conversion of chemical energy into thermal energy
  done clear
  D)
  conversion of chemical energy into electrical energy
  done clear
  View Answer play_arrow

• question_answer16)
  Which of the following is correct statement-
  A)
  Conductivity & molar conductivity of solution increase on dilution
  done clear
  B)
  Voltage of button cell remain unchanged throughout its life time
  done clear
  C)
  On electrolysis of aqueous \[CuS{{O}_{4}}\] using platinum electrode its concentration \[[C{{u}^{2+}}]\] remain constant
  done clear
  D)
  On electrolysis of aqueous \[NaCl,\] solution becomes acidic
  done clear
  View Answer play_arrow

• question_answer17)
  The resistance of 0.1N acetic acid when measured in a cell with cell constant \[1.5\,c{{m}^{-1}}\] is \[5.250\,\Omega \]. The value of \[{{\lambda }_{eq}}\] of \[0.1\,N\,AcOH\] is
  A)
  60
  done clear
  B)
  90
  done clear
  C)
  18.4
  done clear
  D)
   0.023    
  done clear
  View Answer play_arrow

• question_answer18)
  A cell diagram shown below contains one litre of Buffer solution \[HA(p{{K}_{a}}=8)\] and NaA in both compartment. What is the cell emf?
  A)
  0.81 V
  done clear
  B)
  0.071 V 
  done clear
  C)
  0.0591 V
  done clear
  D)
  1.182 V
  done clear
  View Answer play_arrow

• question_answer19)
  Given the following molar conductivities at \[{{250}^{o}}C;HCl,425\,{{\Omega }^{-1}}c{{m}^{2}}mo{{l}^{-1}};\]\[NaCl\,\,125{{\Omega }^{-1}}\]\[c{{m}^{2}}mo{{l}^{-1}}\]NaC (sodium crotonate),  \[82\,{{\Omega }^{-1}}c{{m}^{2}}mo{{l}^{-1}};\] what is the ionisation constant of crotonic acid? If the conductivity of a 0.001 M crotonic acid solution is \[3.82\times {{10}^{-4}}{{\Omega }^{-1}}c{{m}^{-1}}\]?
  A)
  \[1.5\times {{10}^{-4}}\]
  done clear
  B)
  \[1.11\times {{10}^{-5}}\]
  done clear
  C)
  \[2.11\times {{10}^{-5}}\]
  done clear
  D)
  \[1.8\times {{10}^{-5}}\]
  done clear
  View Answer play_arrow

• question_answer20)

  Given

  (i) \[Mn{{O}_{4}}^{-}+8{{H}^{+}}+5{{e}^{-}}\xrightarrow{{}}\]\[M{{n}^{2+}}+4{{H}_{2}}\,O\]

  (ii) \[Mn{{O}_{2}}+4{{H}^{+}}+2{{e}^{-}}\xrightarrow{{}}\]\[M{{n}^{2+}}+2{{H}_{2}}\,O{{E}^{0}}={{x}_{2}}V\]

  Find \[{{E}^{0}}\] for the following reaction

  \[Mn{{O}_{4}}^{-}+4{{H}^{+}}+3{{e}^{-}}\xrightarrow{{}}Mn{{O}_{2}}+2{{H}_{2}}\,O\]

  A)
  \[{{x}_{2}}-{{x}_{1}}\]
  done clear
  B)
  \[{{x}_{1}}-{{x}_{2}}\]           
  done clear
  C)
  \[\frac{5{{x}_{1}}-2{{x}_{2}}}{3}\]
  done clear
  D)
  \[\frac{2{{x}_{1}}-5{{x}_{2}}}{3}\]
  done clear
  View Answer play_arrow

• question_answer21)
  3F of electricity passes through three electrolytic cells connected in series containing  \[A{{g}^{+}},C{{a}^{2+}}\] and \[A{{l}^{3+}}\] ions, respectively. The molar ratio in which the three metal ions are liberated at the electrodes is
  A)
  1 : 2 : 3
  done clear
  B)
  2 : 3 : 1 
  done clear
  C)
  6 : 3 : 2
  done clear
  D)
  3 : 4 : 2
  done clear
  View Answer play_arrow

• question_answer22)
  Match List I with List II and select the correct answer using the code given below the lists:

  List I	List II
  \[Zn|Z{{n}^{2+}}(0.01M)|\,\]\[|Z{{n}^{2+}}(0.1M)|Zn\]	(p) primary cell
  1 Coulomb	(q) Secondary cell
  Dry Cell	(r) \[6.24\times {{10}^{18}}\]electrons
  Lead storage cell	(s) Concentration cell

  A)
  A-s,       B-r,       C-p,      D-q                
  done clear
  B)
  A-p,      B-q,      C-r,       D-s
  done clear
  C)
  A-q,      B-r,       C-s,       D-p                
  done clear
  D)
  A-s,       B-p,      C-q,      D-r
  done clear
  View Answer play_arrow

• question_answer23)
  Which of the following graphs are correct for strong electrolyte AD and AB.
  A)
   
  done clear
  B)
  
  done clear
  C)
   
  done clear
  D)
   
  done clear
  View Answer play_arrow

• question_answer24)
  Salts of A (atomic weight: 7), B (atomic weight: 27), and C (atomic weight: 48) were electrolyzed under identical condition using the same quantity of electricity. It was found that when 2.1 got A was deposited, the weights of B and C deposited were 2.7 and 7.2 g, respectively. The valencies of A, B and C, respectively are:
  A)
  3, 1 and 2
  done clear
  B)
  1, 3 and 2   
  done clear
  C)
  3, 1 and 3
  done clear
  D)
  2, 3 and 2
  done clear
  View Answer play_arrow

• question_answer25)

  The temperature coefficient of a cell whose operation is based on the reaction

  \[Pb(s)+HgC{{l}_{2}}(aq)\xrightarrow{{}}PbC{{l}_{2}}(aq)+Hg(l)\]

  \[{{\left( \frac{dE}{dT} \right)}_{p}}=1.5\times {{10}^{-4}}V/K\,at\,298K\]

  The change in entropy (in J/K mol) during the operation is:

  A)
  8627
  done clear
  B)
  57.9      
  done clear
  C)
  28.95
  done clear
  D)
  14.475
  done clear
  View Answer play_arrow

• question_answer26)

  The electrolysis of acetate solution produces ethane according to reaction:

  \[2C{{H}_{3}}CO{{O}^{-}}\xrightarrow{{}}{{C}_{2}}{{H}_{6}}(g)+2C{{O}_{2}}(g)+2{{e}^{-}}\]

  The current efficiency of the process is 80%. What volume of gases would be produced at \[\text{27}{}^\circ \text{C}\] and 740 torr, if the current of 0.5 A is passed through the solution for 96.45 min?

  A)
  6.0 L
  done clear
  B)
  0.60 L   
  done clear
  C)
  1.365 L
  done clear
  D)
  0.91 L
  done clear
  View Answer play_arrow

• question_answer27)
  A hydrogen electrode placed in a buffer solution of \[C{{H}_{3}}COONa\] and acetic acid in the ratio x : y and y : x has electrode potential value \[{{E}_{1}}\] volts and \[{{E}_{2}}\] volts, respectively at \[\text{25}{}^\circ \text{C}\]. The \[p{{K}_{a}}\] value of acetic acid is (\[{{E}_{1}}\] and \[{{E}_{2}}\] are oxidation potential):
  A)
  \[\frac{{{E}_{1}}+{{E}_{2}}}{0.118}\]
  done clear
  B)
  \[\frac{{{E}_{2}}-{{E}_{1}}}{0.118}\]
  done clear
  C)
  \[-\frac{{{E}_{1}}+{{E}_{2}}}{0.118}\]
  done clear
  D)
  \[\frac{{{E}_{1}}-{{E}_{2}}}{0.118}\]
  done clear
  View Answer play_arrow

• question_answer28)
  Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0.1 M is 100 ohm. The conductivity of this solution is 1.29 S/m. Resistance of the same cell filled with 0.02 M of the same solution if the electrolyte is 520 ohm. The molar conductivity of 0.02 M solution of electrolyte would be:
  A)
  \[124\times {{10}^{-4}}S-{{m}^{2}}/mol\]
  done clear
  B)
  \[1240\times {{10}^{-4}}S-{{m}^{2}}/mol\]
  done clear
  C)
  \[1.24\times {{10}^{-4}}S-{{m}^{2}}/mol\]
  done clear
  D)
  \[12.4\times {{10}^{-4}}S-{{m}^{2}}/mol\]
  done clear
  View Answer play_arrow

• question_answer29)
  The standard electrode potential for the following reaction is +1.33V. What is the potential at \[pH=2.0\]? \[C{{r}_{2}}{{O}_{7}}^{2-}(aq.1M)+14\,{{H}^{+}}(aq)+6{{e}^{-}}\xrightarrow{{}}\] \[2C{{r}^{3+}}(aq.\,1\,M)+7{{H}_{2}}O(\ell )\]
  A)
  +1.820 V
  done clear
  B)
  +1.990 V          
  done clear
  C)
  +1.608 V
  done clear
  D)
  +1.0542 V
  done clear
  View Answer play_arrow

• question_answer30)

  For the following cell reaction

  \[Pb(s)+H{{g}_{2}}S{{O}_{4}}(s)PbS{{O}_{4}}(s)+2Hg(l)\] \[E_{cell}^{o}=0.92V\]

  \[{{K}_{sp}}(PbS{{O}_{4}})=2\times {{10}^{-8}},\]\[{{K}_{sp}}(H{{g}_{2}}S{{O}_{4}})=1\times {{10}^{-6}}\]

  Hence, \[{{E}_{cell}}\] is

  A)
  0.92 V
  done clear
  B)
  0.89 V
  done clear
  C)
  1.04 V
  done clear
  D)
  0.95 V
  done clear
  View Answer play_arrow

• question_answer31)
  Zn-Hg is prepared by electrolysis of aqueous \[ZnC{{l}_{2}}\] using Hg cathode (9g). How much current is to be passed through \[ZnC{{l}_{2}}\] solution for 1000 s to prepare a Zn-Hg with 25% Zn by weight (Zn = 65.4):
  A)
  5.6 A
  done clear
  B)
  7.2 A        
  done clear
  C)
  8.85 A
  done clear
  D)
  11.2 A
  done clear
  View Answer play_arrow

• question_answer32)
  For the cell \[Pt|{{H}_{2}}(g)|\] solution \[X||KCI\] (saturated) \[|H{{g}_{2}}C{{l}_{2}}|Hg|\,Pt\] the observed EMF at \[25{}^\circ C\] was \[600\text{ }mV.\] When solution X was replaced by a standard phosphate buffer with \[pH=7.00,\] the EMF was \[777\text{ }mV\]. Find the pH of solution X.
  A)
  3
  done clear
  B)
  4           
  done clear
  C)
  5
  done clear
  D)
  6
  done clear
  View Answer play_arrow

• question_answer33)
  The same quantity of electricity was passed through two electrolytic cells containing a salt of metal X and zinc sulphate solution respectively using platinum electrode. 0.468 g of metal X and 1.532 g of Zn were deposited. The equivalent mass of X is (At. wt. of Zn is 65.4 u)
  A)
  9.98 g/equiv
  done clear
  B)
  3.2 g/equiv
  done clear
  C)
  5.9 g/equiv
  done clear
  D)
  0.99 g/equiv
  done clear
  View Answer play_arrow

• question_answer34)
  The standard EMF of a cell having one electron change is found to be 0.591 V at \[\text{25}{}^\circ \text{C}\]. The equilibrium constant of the reaction is:
  A)
  \[1.0\times {{10}^{30}}\]
  done clear
  B)
  \[1.0\times {{10}^{5}}\]          
  done clear
  C)
  \[1.0\times {{10}^{10}}\]
  done clear
  D)
  \[1.0\times {{10}^{1}}\]
  done clear
  View Answer play_arrow

• question_answer35)

  Consider following sets:

  Blue colour solution changes to colourless (or fades) in

  A)
  I, II, III
  done clear
  B)
  I, II
  done clear
  C)
  II, III
  done clear
  D)
  I, III
  done clear
  View Answer play_arrow