ECAT Pre Engineering Chemistry Chapter 10 MCQ Test With Answer

During electrolysis, the reaction that takes place at cathode is :

• Reduction A
• Both (a) and (c) B
• Oxidation C
• No reaction occurs D

Electrolytes in the form of solution or in the fused state have the ability to conduct :

• Light. A
• Electricity. B
• Ions. C
• Electrons. 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

In the reaction K₂Cr₂O₇+ HCl + CrCl₃+ Cl₂+ H₂O the element which is reduced is

• K A
• Cl B
• Cr C
• H D

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

• H⁺

  A

• Na⁺

  B

• OH^-

  C

• Cl^-

  D

A dry alkaline cell has porous Zn anode and MnO₂as cathode the electrolyte used is

• Ca(OH)₂ A
• NaOH B
• KOH C
• NH₄OH D

F₂, Cl₂, Br₂and l₂lie below SHE is the Electro chemical series that is why these

• Undergo reduction A
• Undergo oxidation B
• Liberate H₂gas with steam C
• None of these D

The standard EMF of Daniel cell is 1.10 volt. The maximum electrical work obtained from the Daniel cell is

• 212.3 kJ A
• 175.4 kJ B
• 106.15 kJ C
• 53.07 kJ D

96500 C electricity is passed through CuSO₄. The amount of copper precipitated is

• 0.25 mole A
• 0.5 mole B
• 1.0 mole C
• 2.00 mole D

Electrochemical series is a list of element S arranged into the increasing order of their

• Standard oxidation potential A
• Standard reduction potential B
• Cell voltage C
• Ionization potential D

The process of electrical coating of one metal on another to protect, decorate or to have greater resistance to corrosion is called

• Electroplating A
• Electrolysis B
• Conduction C
• Induction D

An electrolyte

• Forms complex ions solution A
• Gives ions only when electricity is passed B
• Possesses ions even in solid state C
• Gives ions only when dissolved in water D

The conductivity of strong electrolyte

• Increases on dilution slightly A
• Does not change on dilution B
• Decreases on dilution C
• Depends on density of electrolyte it self D

Which of the following yield both hydrogen and chlorine on electrolysis:

• Electrolysis of acidified water. A
• Electrolysis of molten NaCl B
• Electrolysis of aqueous NaCl C
• Electrolysis of saline water D

The art of electroplating was given by

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

A cell constant is generally found by measuring the conductivity of aqueous solution of

• BaCl₂ A
• KCl B
• NaCl C
• MgCl₂ 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

Which one of the following reactions is not spontaneous

• 
  A
• 
  B
• 
  C
• 
  D

Time required to deposit one millimole of aluminium metal by the passage of 9.65 amperes through molten electrolyte containing aluminium ion is

• 30 s A
• 10 s B
• 30,000 s C
• 10,000 s D

The voltaic or galvanic cells which cannot be recharged are called

• Primary cells A
• Secondary cells B
• Infinite cells C
• Fuel cells D

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

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

Which of the following is a strong electrolyte?

• Ca(NO₃)₂ A
• HCN B
• CH₃COOH C
• NH₄OH D

In electronic watches or electronic calculators the tiny batteries used are

• Alkaline battery A
• NICAD battery B
• Fuel cell C
• Silver oxide battery D

• Cu A
• H B
• N C
• O D

In an electrolytic cell, the electrons flow from :

• Cathode to anode or opposite A
• Cathode to anode B
• Anode to cathode C
• Random flow 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

The oxidation number of H is -1 in the compound

• H₂O A
• H₃BO₃ B
• NaOH C
• NaH D

• Adding H₂O and H⁺ions A
• Adding OH^-ions B
• Adding O²molecules C
• Adding O atoms 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