ECAT Pre Engineering Chemistry Chapter 10 MCQ Test With Answer

Which statement is incorrect for NICAD battery

• The electrolyte is alkali A
• Cd acts as anode B
• MnO₂acts as electrolyte C
• NiO₂acts as cathode D

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

• 0.142 cm^-1 A
• 0.66 cm^-1 B
• 0.916 cm^-1 C
• 1.12 cm^-1 D

The cathodic reaction in the electrolysis of dill H₂SO₄with Pt electrodes

• Reduction A
• Oxidation B
• Both oxidation and reduction C
• neither oxidation or reduction D

The cell in which a non-spontaneous redox reaction takes place as a result electricity is known as :

• Electrolytic cell. A
• Voltaic cell. B
• Daniel cell. C
• Dry cell. D

Cell potential depends upon :

• Concentration of ions A
• Nature of electrolyte B
• Temperature C
• All of above D

96500 C of electricity liberates from CuSO₄solution

• 63.5 g of Cu A
• 31.75 g of Cu B
• 96500 g of Cu C
• 100 g of Cu D

Fe can displace Cu form CuSO4solution because

• Fe is ferromagnetic A
• Fe is below Cu in electrochemical series B
• Fe is above Cu in electrochemical series C
• Fe exists in divalent oxidation state D

• A strong reducing agent A
• A strong oxidising agent B
• Better oxidising agent than hydrogen C
• Less reducing agent than hydrogen D

Which statement is incorrect for balancing of redox reactions by ion-electron method

• The reaction is splitted into two half reactions A
• H₂O and H⁺ions are added for acidic or neutral reaction to balance O and H atoms B
• To balance H, HCi, is added C
• To balance O and H in the alkaline reaction OH^-added D

• Iodine can oxidise iron A
• Bromine can oxidise iron B
• Iodine can oxidise bromine C
• Iron can oxidise bromine D

The art of electroplating was given by

• Faraday A
• Edison B
• Thomas Gradam C
• Brugan D

Electrochemistry is concerned with the conversion of electrical energy into chemical energy in :

• Galvanic cell A
• Electrolytic cell B
• Voltaic cell C
• Both (a) and (c) D

An electrochemical cell is based upon

• Acid-base reaction A
• Redox reaction B
• Nuclear reaction C
• None of the above D

The equivalent conductivity of 0.1 M week acid is 100 times less than at infinite dilution. The degree of dissociation is

• 100 A
• 10 B
• 0.01 C
• 0.001 D

The reference calomel electrode is made from which of the following?

• ZnCl₂ A
• CuSO₄ B
• Hg₂Cl₂ C
• HgCl₂ D

Out of Cu, Ag, Fe and Zn the metal which can displace all others from theri salt solution is

• Ag A
• Cu B
• Zn C
• Fe D

A cell in which spontaneous redox reaction generates an electric current is called

• Electrolytic cell A
• Electrochemical cell B
• Voltaic or Galvanic cell C
• Biological cell D

Reduction or oxidation potential of standard hydrogen electrode is :

• 0.0 Volt A
• 0.8Volt B
• 1.0Volt C
• 1.8Volt D

When fused PbBr2 is electrolyzed :

• Lead appears at anode. A
• Lead appears at cathode. B
• Bromine appears at cathode. C
• Lead appears at both electrodes. D

In electrolytic cells, the chemical changes may be :

• Either spontaneous or non-spontaneous A
• Always spontaneous B
• Always non-spontaneous C
• More spontaneous and less non-spontaneous. D

During electrolysis, electrons are :

• Lost by anions and gained by cations A
• Gained by anions and lost by cations B
• Gained only C
• Lost only D

Best way to prevent rusting of iron is by

• Making iron cathode A
• Putting it in saline water B
• Both of these C
• None of these D

Strong oxidizing agents have

• Greater positive value of standard reduction potential A
• Lesser positive value of standard B
• Greater negative value of standard C
• None of these D

Which statement is correct for the fuel cells

• These cells operate at low temperature A
• These cells operate at low temperature B
• No catalyst used for the formation of water C
• MnO₂is used as electrolyte D

Which one of the following reaction takes place spontaneously

• 
  A
• 
  B
• 
  C
• 
  D

Calculate the amount of charge flowing in 2 minute in a wire of resistance 10Ωwhen a potential difference of 20 V is applied

• 120 C A
• 240 C B
• 20 C C
• 4 C D

When aqueous NaCl is electrolyzed, which of the following ions get discharged at anode :

• H⁺

  A

• Na⁺

  B

• OH^-

  C

• Cl^-

  D

The two half cells of a galvanic cell are connected by

• Ammeter A
• Salt bridge B
• Hydrogen electrode C
• Copper electrode D

Zn does not displace Mg from MgSO₄solution because

• Zn is more electropositive than Mg A
• Zn is below Mg in electropositive series B
• Zn is above Mg in electrochemical series C
• Zn is trivalent Mg is divalent D

Standard reduction electrode potential of three metals A, B and C are erespectively + 0.05 V, -3.0 and -1.2V. The reducting power of

• B > C > A A
• A > B > C B
• C > B > A C
• A > C > B D