ECAT Chemistry Chapter 10 Electrochemistry

When quantity of electricity passed is one faraday then the mass deposited at the electrode is equal to

• One gm, atomic weight A
• One gm, Equivalent B
• Eletrochemical equivalent C
• None of the above 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

A standard hydrogen electrode (S.H.E) consists of a platinized platinum electrode dipped in 1 molar solution of H⁺ions and hydrogen gas is passed at a pressure of

• One pascal A
• One kilo pascal B
• One atmoshpere C
• Then atmoshpere D

Coinage metals like Au, Pt, Ag and Cu are the least reactive metals and don't liberate H₂gas when treated with acids because

• These have very high positive values of reduction potentials A
• These have very high negative values of reduction potentials B
• Their ionization potentials are lowest C
• Their reduction potentials are close to SHE D

The galvanic or voltaic cells which are rechargeable called as

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

The number of coulombs required for the deposition of 107.870 g of silver is

• 96500 A
• 48250 B
• 193000 C
• 10000 D

During electrolysis of KNO₃, H₂is evolved

• Anode A
• Cathode B
• Both a and b C
• None D

The two half cells of a galvanic cell are connected by

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

Which of the following is the use of electrolysis?

• Eletrorefining A
• Electroplating B
• Both A and B C
• None of the above 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

Pick out the wrong statement. In electrochemical cell

• Electrons are released at anode A
• Cathode is regarded as negative electrode B
• Chemical energy is converted into electrical energy C
• Salt bridge maintains the electrical neutrality of the solution D

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

The reduction potential to copper electrode is +0.34 V and that of Zn electrode is -0.76 V. when these two are coupled the e.m.f. of the cell is

• -0.42 V A
• +0.42 B
• -1.10 V C
• +1.10 V D

An electrochemical cell is based upon

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

While balancing an equation by ion electron method, the number of oxygen atoms are balanced by

• OH^- A
• H₂O B
• O₂ C
• H⁺ D

What are the products electrolysis of aqueous sodium chloride at two electrodes

• Chlorine at anode and oxygen at cathode. A
• Hydrogen at anode and chlorine at cathode. B
• Chlorine at anode and hydrogen at cathode. C
• Chlorine at anode and sodium at cathode. D

A standard hydrogen electrode is used as standard electrode of which electrode potential is arbitrarily taken as

• +1 A
• -1 B
• 0.1 C
• Zero D

Corrosion reaction are

• Spontaneous redox reaction A
• Non-spontaneous acid-base reactions B
• Spontaneous acid-base reactions C
• None of these 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 function of salt bridge in the galvanic or voltaic cell is to

• Carry out oxidation at anode A
• To carry out reduction at cathode B
• Carry out electrolysis C
• To prevent the net charge accumulation in either of the half cells D

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

• BaCl₂ A
• KCl B
• NaCl C
• MgCl₂ 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

The specific conductance of 0.1 M NaCl solution is 1.06 x 10^-2ohm^-1mol^-1. Its molar conductance in ohm^-1cm²mol^-1is

• 1.06 x 10² A
• 1.06 x 10³ B
• 1.06 x 10⁴ C
• 53 D

• Zn A
• H B
• S C
• O D

In lead accumulator the electrolyte is H₂SO₄solution is

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

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

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

Metals which are above SHE in electrochemical series

• Can liberate H₂from acid A
• Cannot liberate H₂from acid B
• Cannot always liberate H₂from acid C
• None of these D

• Cu A
• H B
• N C
• O D

In the electrolysis of aqueous solution of sodium nitrate, the ions which are reduced at the cathode are

• H₃O⁺ A
• Na⁺ B
• OH^- C
• NO^3- D

Metals like Fe, Mg, Al, Cr, Zn have more negative reduction potentials that is whey

• These don't react with steam A
• These react very slowly with steam to liberate H₂gas B
• These react rapidly with steam to produce the metallic oxides and liberate H₂gas C
• These react with cold water violently D