This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Electrolytic reducation of Al_(2)O_(3) Electrolyte (Al_(2)O_(3)+cryolite) Cathode : fraphite inside Fe -Container Pick out the statement which is wrong if anode is made of nikel instesd of graphoite? |
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Answer» ni is costly |
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| 2. |
Electrolytic reduction is used in the extraction of |
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Answer» Magnesium |
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| 3. |
Electrolytic oxidation of H_2SO_4gives rise to the formation of persulphuric acid, H_2S_2O_8.2H_2SO_4 to H_2S_2O_8 + 2H^(+) + 2eIf 4 litres of O_2and 11.2 litres of H_2were produced at NTP, determine the mass of H_2S_2O_8produced. |
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Answer» SOLUTION :`2H_2SO_4to H_2S_2O_8 + H_2` `2H_2O to 2H_2+ O_2` EQ. of `H_2S_2O_8 = ` eq. of `H_2 ` - eq. of `CO_2` 27.72g |
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| 4. |
Electrolytic process is used for the extraction of |
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Answer» Alkali metal |
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| 6. |
Electrolytic conduction differs from metallic conduction in the fact in the case of electrolytic conduction |
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Answer» the resistance increases with INCREASING temperature |
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| 7. |
Electrolytic conduction differs from metallic conduction in that in the case of electrolytic conduction |
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Answer» The RESISTANCE INCREASES with INCREASING temperature |
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| 8. |
Electrolytic cell containing molten nickel chloride and aluminium chloride solutions are arranged in a series. If on passing same current through both the solution, if 18 gm Al is obtained then how much Ni is obtained ? (Atomic mass of Al=27 and Ni=58.5 gm mol^(-1)) |
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Answer» 58.5 gm `Al^(3+)+3e^(-) to Al_((S))` So, 3 MOL `e^(-) to 1` mol AI So, 27 gm Al required 3 F CURRENT. So for 18 gm Al, amount of electricity `=(18xx3)/(27)=2F` (ii) 2F current is also PASSED through `Ni^(2+)` solution as it is in series. `Ni^(2+)+2e^(-) to NI_((S))` |
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| 9. |
Electrolytic cell is used to convert |
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Answer» ELECTRICAL energy to chemcial energy |
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| 10. |
Electrolytic cell and Electrochemical cell or Galvanic cell or Voltaic cell. |
| Answer» Solution :`{:("ELECTROLYTIC CELL","electrochemical cell (Galvanic cell or Voltaic cell)"),("1. This device is used to bring about a non-spontaneous chemical REACTION by passing an electric current.","1. This device is used to produce elexctrical energy by spontaneous chemical reaction.,"),("2. It is used to bring about a chemical reaction GENERALLY FRO the dissocition (electrolysis) of compounds.","2. It is used to generate electrocity."),("3. In this cell, electrical energy is converted into chemical energy.","3. In this cell, chemical energy is converted into electrical energy."),("4. In this cell, the cathode is negative and anode is positive.","4. In this cell, the cathode is positive and the anode is negative."),("5. Electrolytic cells are irreversible.","5. Electrochemical cells are reversible".):}` | |
| 11. |
{:("Electrolyte:",KCl,KNO_(3),HCl,NaOAc,NaCl),(wedge^(oo)(Scm^(2)mol^(-1)),149.9,145.0,426.2,91.0,126.5):} Calcualte wedge_(HOAc)^(oo) using appropriate molar conductances of the electrolytes listed above at infinite dilution in H_(2)O at 25^(@)C. |
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Answer» 517.2 |
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| 12. |
{:("Electrolyte","Battery"),((i)NH_(4)Cl+ZnCl_(2)+H_(2)O,"(a) Mercury button cell"),("(ii) Paste of KOH and ZnO","(b) Lithium - ion battery"),("(iii) 38% by mass of "H_(2)SO_(4),"(c ) Leclanche cell"),("(iv) Lithium salt in an organic solvent","(d) Lead storage battery"):} |
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Answer» `{:(A,B,C,D),(c,a,d,b):}` |
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| 13. |
Electrolytes when dissolved in water dissociate into ions, because : |
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Answer» They are unstable |
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| 14. |
Electrolyte when dissolved in water dissociate into their constituent ions. The degree of dissociation of an electrolyteincreases with |
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Answer» Increasing concentration of the electrolyte |
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| 15. |
Electrolysis rules of Faraday states that mass deposited on electrode is proportional to |
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Answer» `m oo l^2` |
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| 16. |
Electrolysis temperature is maximum for |
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Answer» `AsH_(3)` |
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| 17. |
Electrolyte can conduct electricity because |
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Answer» |
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| 18. |
Electrolyte can conduct electricity because ___________. |
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Answer» their molecules CONTAIN unpaired electrons, which are mobile |
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| 19. |
Electrolysis of water with 1 faraday electricity gives |
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Answer» 1 mole of oxygen |
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| 20. |
Electrolysis of water with 1 Faraday electricity gives : |
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Answer» 1 MOLE of OXYGEN |
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| 21. |
Electrolysis of queous potassium sulphate containing litmus, develop red colour at anode and blue colour at cathode. Why ? |
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Answer» Solution :During the electrolysis of aqueous `K_2SO_4` , the chemical CHANGES involved are, At anode (oxidation of water) = `2H_2O(L) to O_2 + 4E^(-) + 4H^(+)(aq)` At CATHODE (reduction of water) = `2H_2O (l) + 2e^(-) to H_2(g) + 2OH^(-)(aq)` Solution is ACIDIC around anode and litmus is red. Solution is basic around cathode and litmus is blue. |
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| 22. |
Electrolysis of molten sodium chloride leads to the formation of |
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Answer» `Na` and `H_(2)` |
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| 23. |
Electrolysis of molten NaCl leads to the formation of : |
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Answer» SODIUM and oxygen |
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| 24. |
Electrolysis of KBr (aq) gives Br_(2) at anode but of KF (aq) does not give F_(2) . Give reason for disparity in behaviour. |
| Answer» Solution :`L_(F_(2)//F^(-))^(@)`has the HIGHEST reduction potential. THEREFORE, `F_(2)`is not liberated. Reduction potential of `O_(2)`is higher than that of `Br_(2)` . Thus, ELECTROLYSIS of KBr (aq) gives `Br_(2)`and not `O_(2)` | |
| 25. |
Electrolysis of fused KCl.MgCl_2.6H_2O gives: |
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Answer» POTASSIUM only |
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| 26. |
Electrolysis of dilute aqueous solution of KCl gives? |
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Answer» `O_2` at anode |
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| 27. |
Electrolysis of dilute aqueous NaCl solution was carried ut be passing 10 milli ampere current. The time required to liberate 0.01 mol of H_(2) gas at the cathode is (1Faraday=96500 C mol^(-1)) |
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Answer» `9.65xx10^(4)sec` `H_(2)OhArrH^(+)+OH^(-)` `H^(+)+e^(-)to(1)/(2)H_(2)` Thus, 0.5 mole of `H_(2)` is liberated by 1F=96500C `therefore0.01V` mole of `H_(2)` will be liberated by CHARGE `=(96500)/(0.5)xx0.01=1930C` `Q=Ixxt` or `t=(Q)/(I)=(1930C)/(10xx10^(-3)A)` |
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| 28. |
Electrolysis of dilute aqueous sodium chloride solution was carried out by passing 10 milliampere current. The time required to liberate 0.01mol of H_2 gas at the cathode is (1 Faraday= 96500 C mol^(-1)). |
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Answer» `9.65 XX 10^4s` |
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| 29. |
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)) |
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Answer» `9.65xx10^(4)`sec Equivalent of `H_2` PRODUCED `=(1xxt(sec))/(9)` `0.01xx2=(10xx10^(-3)t)/(96500)=96500xx2=t` `19.3xx10^(4)sec=1`. |
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| 30. |
Electrolysis of dilute aqueous NaCl solution was carried out by passing 10 rnilli ampere current. The time required to liberate 0.01 mole of H_(2) gas at the cathode is (1 Faraday =96500 C mol^(-1) ) |
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Answer» `9.65 xx10^(4)SEC` `H^(*) * c ^(*) * * 1/2 H_(2)` `therefore0.5` mole of `H_(2)` is liberated by 1 `F = 96500C 0.01 ` mole of `H_(2)` will beliberated by `=(96500)/(0.5)0.01""=1930C` `Q=1xx1` `t * (Q)/(T)* (1930)/(10 * 10^(*3)A)* 19.3* 10^(4)sec` |
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| 31. |
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 F = 96500 C "mol"^(-1)) |
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Answer» `9.56xx10^(4)SEC` |
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| 32. |
Electrolysis of dilute aqueous NaCl solution was carried out by passing 10 milli ampere current. The time required to liberated 0.01 mole of H_(2) gas at cathode is: ("1 faraday =96500"C mol"^(-1)). |
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Answer» `9.65xx 10^(4)"sec"` `W=(LT E)/(96500)` `0.02=(10 xx 10^(-3) xx t xx 1)/(96500)` `t=19.3 xx 10^(4)" sec"`. |
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| 33. |
Electrolysis of dilute aqueous NaCl solution was carried out by passing 10 milli-ampere current. The time required to liberate 0.01 mole of H_(2) gas at the cathode is : (1 faraday = 96500 C mol^(-1)) |
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Answer» `9.65 XX 10^(4)` SEC `0.01 xx 2 = (10 xx 10^(-3) xx t)/(96500)` ` t = 19.3 xx 10^(4)` sec |
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| 34. |
Electrolysis of concentrated aqueous solution of an alkali salt of fatty acid gives : |
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Answer» Alkanes |
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| 35. |
Electrolysis of cold concentrated aqueous solution of potassium succinate yields |
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Answer» Ethane |
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| 36. |
Electrolysis of concentrated solution of potassium acetate gives : |
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Answer» ETHANE |
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| 37. |
Electrolysis of cold conc. Aqueous solution of potassium succinate yields |
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Answer» Ethane |
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| 38. |
Electrolysis of cold concentrated aqueous solution of potassiumsuccinate yields: |
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Answer» ETHANE |
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| 39. |
Electrolysis of brine gives |
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Answer» `Cl_(2)` Cathode `: H_(2) O overset( 2e) ( rarr) H_(2) + 2OH^(-) `( REDUCTION) `2Na^(+)+2OH^(-) rarr 2NaOH` |
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| 40. |
Electrolysis of aqueous solution of Na_(2)SO_(4) is carried out in presence of graphite electrode. |
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Answer» Na is OBTAINED at cathode. `H_(2)` gas is obtained at cathode on reduction of water, no reduction of `Na^(+)` is OBSERVED on cathode. `2H_(2)O_((L))+2e^(-) to H_(2(g))+2OH_((aq))^(-)` `O_(2)` is obtained at anode on OXIDATION of water, no oxidation is observed on `SO_(4)^(2-)`. `H_(2)O_((l)) to (1)/(2)O_(2(g))+2H_((aq))^(+)+2e^(-)`. |
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| 41. |
Electrolysis of aqueous HCl solution produces |
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Answer» `H_(2)` GAS at the anode |
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| 42. |
Electrolysis of aqueous HCI solution produces |
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Answer» |
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| 43. |
Electrolysis of aqueous alkali metal chloride does not liberatemetal . Why ? |
| Answer» SOLUTION :In aqueous solutions, both sodium cation and water MOLECULES are present around cathode. Water is PREFERENTIALLY reduced to liberate HYDROGEN, since metal cation is stable. | |
| 44. |
Electrolysis of aqueous copper sulphatesolution liberateswhich of the following gasesat the anodes ? |
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Answer» `SO_(3)^(-)` |
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| 45. |
Electrolysis of aqueous HF produces O_2 at anode but not F_2 Explain. |
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Answer» Solution :In aqueous solution , fluoride `(F^(-))` is very stable Electrolysis of aqueous fluoride liberates oxygen , due to the preferential OXIDATION of WATER . `2H_(2)Oto4e^(-)+4H^(+)+O_(2)` |
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| 46. |
Electrolysis of aq solution of brine gives |
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Answer» `Cl_(2)` at CATHODE `: 2H_(2) O + 2e^(-) rarr 2OH^(-) + H_(2) UARR` `2Na^(+) + 2HO^(-) rarr 2NaOH` at anode `: 2Cl^(-) rarr CL^(2) uarr` |
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| 47. |
Electrolysis of an aqueous solution of sodium chloride produces____at the cathode and ____at the anode. |
| Answer» SOLUTION :`H_(2),Cl_(2)` | |
| 48. |
Electrolysis of an aqueous solution of copper sulphate using platinum electrodes produces____ at the cathode and ___at the anode. |
| Answer» SOLUTION :`CU,O_(2)` | |
| 49. |
Electrolysis of an aqueous solution of AgNO_(3) with silver electrodes produces ul((i)) at cathode while ul((ii)) ions are dissolved from anode. When Pt electrodes are used ul((iii)) is produced at anode and ul((iv)) at cathode. |
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Answer» `{:("(i)", "(ii)","(III)","(IV)"),(H_(2), NO_(3)^(-) , OH^(-) , H_(2)):}` |
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| 50. |
Electrolysis of an aqueous solution of AgNO_3 with silver electrodes produce __(i)___ at cathode while ___(ii)___ ions are dissolved from anode. When Pt electrodes are used ____(iii)___ is produced at anode ___(iv)___ at cathode. |
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Answer» `{:("(i)","(II)","(III)","(iv)"),(H_2,NO_3^(-) , OH^(-), H_2):}` |
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