Redox Reactions and Electrochemistry Quizzes | Year 12 Chemistry

Question 1

Which factor does NOT affect the rate of a redox reaction?

Accepted Answer

Identity of the metal ion in the reactants

Answer

Concentration of reactants

Answer

Temperature

Answer

Surface area of reactants

Question 2

Which of the following is NOT an electrochemical device?

Accepted Answer

Capacitor

Answer

Galvanic cell

Answer

Electrolytic cell

Answer

Fuel cell

Question 3

Which of the following is the correct half-reaction for the oxidation of bromide ions to bromine?

Accepted Answer

2Br- → Br2 + 2e-

Answer

Br2 + 2e- → 2Br-

Answer

Br- + e- → Br

Answer

Br → Br+ + e-

Question 4

Which of the following is NOT a characteristic of redox reactions?

Accepted Answer

Always occur in acidic solutions

Answer

Involve the transfer of electrons

Answer

Oxidation is the loss of electrons

Answer

Reduction is the gain of electrons

Question 5

Which factor does NOT affect the rate of a redox reaction?

Accepted Answer

Strength of an externally applied magnetic field

Answer

Concentration of reactants

Answer

Temperature

Answer

Surface area of reactants

Question 6

Which factor does NOT influence the rate of a reaction?

Accepted Answer

Volume of the reaction vessel

Answer

Temperature

Answer

Surface area of reactants

Answer

Concentration of reactants

Question 7

In redox reactions, oxidation is the process of:

Accepted Answer

Losing electrons

Answer

Gaining electrons

Answer

Gaining protons

Answer

Losing protons

Question 8

In the reaction 2Fe2+ (aq) + Cl2 (g) -> 2Fe3+ (aq) + 2Cl- (aq), which species is the oxidizing agent?

Accepted Answer

Cl2

Answer

Fe2+

Answer

Fe3+

Answer

Cl-

Question 9

In a fuel cell, what is the primary function of the proton exchange membrane?

Accepted Answer

Separates anode and cathode, allowing proton flow while preventing reactant/product mixing.

Answer

Catalyzes electrochemical reactions at anode and cathode.

Answer

Generates electrical current through a chemical reaction.

Answer

Stores fuel and oxidant before electrochemical reactions.

Question 10

In the Nernst equation, E = E° - (RT/nF)lnQ, what does 'Q' represent?

Accepted Answer

The reaction quotient, similar to the equilibrium constant for the redox reaction

Answer

The standard cell potential of the electrochemical cell

Answer

The concentration of reactants in the electrochemical cell

Answer

The temperature of the electrochemical cell

Question 11

In an electrolytic cell, what is the main function of the diaphragm or separator?

Accepted Answer

Prevent the mixing of anode and cathode products

Answer

Enhance the electrical conductivity of the solution

Answer

Provide structural support for the electrodes

Question 12

What is the distinctive feature of fuel cells that enables them to generate electricity?

Accepted Answer

Ion-conducting membrane

Answer

Concentrated reactants

Answer

High operating temperatures

Answer

Sound production

Question 13

In the reaction Cu + 2Ag+ → Cu2+ + 2Ag, which species is oxidized?

Accepted Answer

Cu

Answer

Ag+

Answer

Cu2+

Answer

Ag

Question 14

Which of the following is a disadvantage of lead-acid batteries?

Accepted Answer

Environmental concerns

Answer

High energy density

Answer

Long lifespan

Answer

Low maintenance

Question 15

What is the purpose of a salt bridge in an electrochemical cell?

Accepted Answer

To maintain electrical neutrality

Answer

To provide a path for electron flow

Answer

To act as a catalyst

Answer

To prevent the mixing of solutions

Question 16

What is the oxidation state of nitrogen in HNO3?

Accepted Answer

+5

Answer

-3

Answer

+3

Answer

-5

Question 17

Identify the reducing agent in the following options:

Accepted Answer

Na

Answer

Cl2

Answer

F2

Answer

MnO4-

Question 18

In an electrochemical cell, what is the primary function of a salt bridge?

Accepted Answer

Maintain electrical balance within the system

Answer

Prevent mixing of solutions

Answer

Function as a reducing agent

Answer

Enhance the voltage of the cell

Question 19

Which factor does NOT influence the rate of an electrochemical reaction?

Accepted Answer

Density of the solution

Answer

Concentration of reactants

Answer

Temperature

Answer

Surface area of electrodes

Question 20

In a voltaic cell, identify the cathode:

Accepted Answer

Electrode where reduction takes place

Answer

Electrode with positive charge

Answer

Electrode with negative charge

Answer

Electrode where oxidation takes place

Question 21

In a redox reaction, reduction is characterized by which of the following?

Accepted Answer

Gain of electrons

Answer

Loss of electrons

Answer

Increase in oxidation state

Answer

No change in oxidation state

Question 22

Which of the following statements accurately defines oxidation?

Accepted Answer

Loss of electrons

Answer

Gain of electrons

Answer

Loss of hydrogen ions

Answer

Gain of oxygen atoms

Question 23

Determine the oxidation state of sulfur in H2SO4.

Accepted Answer

+6

Answer

+2

Answer

+4

Answer

-2

Question 24

Identify the species acting as a reducing agent in the following reaction: Fe2O3 + 3CO → 2Fe + 3CO2

Accepted Answer

CO

Answer

Fe2O3

Answer

Fe

Answer

CO2

Question 25

What is the standard electrode potential of the standard hydrogen electrode?

Accepted Answer

0.00 V

Answer

1.00 V

Answer

-1.00 V

Answer

2.00 V

Question 26

Describe the primary function of a salt bridge in an electrochemical cell.

Accepted Answer

Maintain electrical neutrality

Answer

Allow electron flow

Answer

Elevate solution conductivity

Answer

Measure current

Question 27

Identify the type of electrochemical cell represented by a car battery.

Accepted Answer

Galvanic cell

Answer

Electrolytic cell

Answer

Fuel cell

Answer

Solar cell

Question 28

Determine the primary gaseous products formed during the electrolysis of water.

Accepted Answer

Hydrogen and oxygen

Answer

Hydrogen and chlorine

Answer

Oxygen and chlorine

Answer

Hydrogen and carbon dioxide

Question 29

Define oxidation in terms of electron transfer.

Accepted Answer

Loss of electrons

Answer

Gain of electrons

Answer

Gain of protons

Answer

Loss of protons

Question 30

Identify the reducing agent in the reaction: 2Fe³⁺ + Sn²⁺ → 2Fe²⁺ + Sn⁴⁺.

Accepted Answer

Sn²⁺

Answer

Fe³⁺

Answer

Fe²⁺

Answer

Sn⁴⁺

Question 31

In a reaction between 1 mole of Fe and 2 moles of HCl, identify the limiting reactant.

Accepted Answer

Fe

Answer

HCl

Answer

Both Fe and HCl

Answer

Neither Fe nor HCl

Question 32

What are the products formed during the electrolysis of water?

Accepted Answer

Hydrogen and oxygen

Answer

Hydrogen and chlorine

Answer

Oxygen and chlorine

Answer

Hydrogen and bromine

Question 33

What is the purpose of a voltmeter in an electrochemical experiment?

Accepted Answer

To measure the potential difference between the electrodes

Answer

To measure the resistance of the circuit

Answer

To determine the polarity of the electrodes

Answer

To control the flow of current in the circuit

Question 34

What is the anode in the electrolysis of water?

Accepted Answer

Graphite rod

Answer

Platinum electrode

Answer

Oxygen gas electrode

Answer

Iron electrode

Question 35

Evaluate the advantages and limitations of redox reactions in developing sustainable energy storage and conversion technologies such as batteries and fuel cells.

Accepted Answer

Zero emissions during operation

Answer

Infinite energy storage capacity

Answer

Low production and maintenance costs

Question 36

Determine the correct oxidation state of nitrogen in nitric acid (HNO3).

Accepted Answer

+5

Answer

0

Answer

+1

Answer

+3

Question 37

Explain the purpose of a salt bridge in an electrochemical cell.

Accepted Answer

Enables ion flow between half-cells

Answer

Prevents mixing of solutions

Answer

Generates electric current

Answer

Measures cell voltage

Question 38

Identify the component that acts as an anode in an electrochemical cell.

Accepted Answer

Oxidized metal

Answer

Reduced non-metal

Answer

Solution with high ion concentration

Answer

Salt bridge

Question 39

What drives a redox reaction?

Accepted Answer

Change in free energy

Answer

Electronegativity difference

Answer

Presence of catalyst

Answer

Concentration of reactants

Question 40

What is the primary purpose of using a voltmeter in an electrochemical experiment?

Accepted Answer

Measure voltage

Answer

Measure current

Answer

Measure ion concentration

Answer

Determine reaction rate

Question 41

Define oxidation in terms of electron transfer

Accepted Answer

Loss of electrons

Answer

Loss of protons

Answer

Gain of electrons

Answer

Gain of protons

Question 42

In the reaction: Fe + 2HCl → FeCl2 + H2, which species undergoes oxidation?

Accepted Answer

Fe

Answer

HCl

Answer

H2

Answer

FeCl2

Question 43

What is the standard electrode potential for the hydrogen electrode?

Accepted Answer

0.00 V

Answer

-1.00 V

Answer

0.50 V

Answer

1.00 V

Question 44

In the electrolysis of water, identify the electrode where oxygen is produced

Accepted Answer

Anode

Answer

Cathode

Answer

Neither electrode

Answer

Both electrodes

Question 45

What is the purpose of a salt bridge in an electrochemical cell?

Accepted Answer

To maintain electrical neutrality while allowing ion flow

Answer

To generate a potential difference

Answer

To prevent the flow of electrons

Question 46

What is the primary use of electrochemical cells?

Accepted Answer

Conversion of chemical energy to electrical energy

Answer

Conversion of electrical energy to chemical energy

Answer

Separation of mixtures

Question 47

Which of the following is a reducing agent?

Accepted Answer

Zn

Answer

Fe3+

Answer

Cu2+

Answer

Ag+

Question 48

The standard electrode potential of the hydrogen electrode is defined as:

Accepted Answer

0.00 V

Answer

-1.00 V

Answer

+1.00 V

Question 49

What is the cathode in the electrolysis of molten NaCl?

Accepted Answer

Graphite rod

Answer

Copper electrode

Answer

Platinum wire

Answer

Silver electrode

Question 50

What is the purpose of a salt bridge in an electrochemical cell?

Accepted Answer

To maintain electrical neutrality

Answer

To act as a catalyst

Answer

To increase the conductivity of the solution

Answer

To prevent the mixing of solutions

Question 51

Which of the following is an application of electrochemistry?

Accepted Answer

Electroplating

Answer

Combustion

Answer

Neutralisation

Answer

Photosynthesis

Question 52

In the reaction: Fe + 2HCl → FeCl2 + H2, which species undergoes oxidation?

Accepted Answer

Fe

Answer

HCl

Answer

H2

Answer

FeCl2

Question 53

Which of the following is the standard electrode potential of the hydrogen electrode?

Accepted Answer

0.00 V

Answer

-2.92 V

Answer

-0.42 V

Answer

+1.00 V

Question 54

Which of the following is an industrial application of electrolysis?

Accepted Answer

Electroplating

Answer

Photosynthesis

Answer

Combustion

Answer

Neutralization

Question 55

What is the oxidation number of sulfur in H2SO4?

Accepted Answer

+6

Answer

+4

Answer

-6

Answer

-2

Question 56

Which of the following is a reducing agent?

Accepted Answer

Zn

Answer

MnO4-

Answer

Cl-

Question 57

Write the half-reaction for the reduction of Cu2+ to Cu.

Accepted Answer

Cu2+ + 2e- → Cu

Answer

Cu2+ → Cu + 2e-

Answer

Cu → Cu2+ + 2e-

Question 58

Which of the following has the highest reduction potential?

Accepted Answer

F2

Answer

Cl2

Answer

Br2

Answer

I2

Question 59

Which of the following is **not** a characteristic of a redox reaction?

Accepted Answer

No change in oxidation state

Answer

Oxidation and reduction occur simultaneously

Answer

Electron transfer

Answer

Change in energy

Question 60

The standard reduction potential of the Ag+/Ag half-cell is +0.80 V. What is the standard oxidation potential of the Ag/Ag+ half-cell?

Accepted Answer

-0.80 V

Answer

+0.80 V

Answer

+1.60 V

Answer

-1.60 V

Question 61

In the electrolysis of aqueous NaCl, what is the product formed at the anode?

Accepted Answer

Chlorine

Answer

Sodium chloride

Answer

Sodium

Answer

Hydrogen

Question 62

Which of the following is NOT an application of electrolysis?

Accepted Answer

Acid-base neutralization

Answer

Water purification

Answer

Production of hydrogen

Answer

Electroplating

Question 63

What type of ion is responsible for carrying current through a molten ionic compound?

Accepted Answer

Ion

Answer

Neutron

Answer

Electron

Answer

Proton

Question 64

Which of the following is NOT a type of fuel cell?

Accepted Answer

Coal-fired power plant

Answer

Hydrogen fuel cell

Answer

Solid oxide fuel cell

Answer

Direct methanol fuel cell