ECAT Pre Engineering Chemistry Chapter 10 MCQ Test With Answer

Matals usually conduct electricity because

• There are mobile electrons in the metallic structure A
• Metals are decomposed by current B
• Metals have high resistance C
• In metals the ions are free to move D

Reduction or oxidation potential of standard hydrogen electrode is :

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

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

The amount of electricity that can deposit 108 g of silver from silver nitrate solution is

• 1 ampere A
• 1 coulomb B
• 1 faraday C
• 2 ampere D

A half reaction can be defines as :

• It always occurs at cathode. A
• Involves only half of a mole of electrolyte. B
• Occurs at one of the electrode. C
• Goes only half way to completion. 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

K,Ca and Li metals may be arranged in decreasing order of their reduction potential as :

• Li, k, Ca A
• Ca, K, Li B
• Li, Ca, K C
• K, Ca, Li 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 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

In lead accumulator the electrolyte is H₂SO₄solution is

• 30% H₂SO₄ A
• 60% H₂SO₄ B
• 80% H₂SO₄ C
• 90% H₂SO₄ D

Which of the following statements is true about Galvanic cell

• Anode is negatively charged A
• Reduction occurs at anode B
• Cathode is positively charge C
• Reduction occurs at cathode 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

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

When fused PbBr₂is electrolyzed

• Bromine appears at he cathode A
• Lead is deposited at the cathode B
• Lead appears at the anode C
• None of these happens D

Silver oxide battery has a voltage of

• 2.0 V A
• 1.5 V B
• 2.5 V C
• 1.0 V D

For spontaneity of a cell, which is correct?

• ΔG = 0,ΔE = 0 A
• ΔG = -ve ,ΔE = 0 B
• ΔG = +ve ,ΔE = 0 C
• ΔG = -ve D

Most metals are conductors of electricity because of the :

• Light weight. A
• Immobility of the electrons. B
• Lustrous surfaces C
• Relatively free movement of their electrons D

What will be the weight of deposited silver on passing 965 coulombs of electricity in solution of AgNO₃?

• 1.08 g A
• 2.16 g B
• 0.54 g C
• 0.27 g D

By using graphite electrode the electrolysis of aqueous solution of NaCI produces at anode

• H₂gas A
• Cl₂gas B
• NaOH C
• No metal 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

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

Corrosion reaction are

• Spontaneous redox reaction A
• Non-spontaneous acid-base reactions B
• Spontaneous acid-base reactions C
• None of these 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

The cell which generates electricity as a result of spontaneous oxidation-reduction reaction is called

• Electrolytic cell A
• Nelson's cell B
• Galvanic cell C
• Down's cell 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

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

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

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

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

When a metal is dipped in 1 molar of its solution at 298 K. then potential set up is called

• Standard electrode potential A
• Electric charge B
• Ionization potential C
• Electroplating D