Electrochemistry Quizzes: Test Your Understanding of Redox Reactions and Electrochemical Cells

Question 1

Which characteristic differentiates a spontaneous redox reaction?

Accepted Answer

Positive cell potential

Answer

Negative cell potential

Answer

Equal cell potential

Answer

Zero cell potential

Question 2

Provide the most accurate definition of an electrochemical cell:

Accepted Answer

A device that harnesses chemical reactions to generate electrical energy

Answer

A device that utilizes electrical energy to drive chemical reactions

Answer

A device designed to measure the concentration of ions in a solution

Answer

A device capable of storing electrical energy

Question 3

An electrochemical cell with a positive cell potential is considered to be:

Accepted Answer

Spontaneous

Answer

Non-spontaneous

Answer

At equilibrium

Answer

Reversible

Question 4

Which factor does NOT affect the EMF of an electrochemical cell?

Accepted Answer

Volume of the cell

Answer

Concentrations of reactants and products

Answer

Temperature

Answer

Nature of the electrodes

Question 5

In a galvanic cell, which electrode is the site of oxidation?

Accepted Answer

Anode

Answer

Cathode

Answer

Reference electrode

Answer

Salt bridge

Question 6

What does the Nernst equation relate?

Accepted Answer

Cell potential to reactant and product concentrations

Answer

Reactant concentrations to reaction rate

Answer

Temperature to cell EMF

Answer

pH to hydrogen ion concentration

Question 7

Which type of electrochemical cell is used for electroplating?

Accepted Answer

Electroplating cell

Answer

Fuel cell

Answer

Galvanic cell

Answer

Concentration cell

Question 8

What does the Faraday constant represent?

Accepted Answer

Charge per mole of electrons

Answer

Current flow per unit time

Answer

Cell potential per unit concentration

Answer

Amount of substance per unit volume

Question 9

Which type of reaction involves electron transfer?

Accepted Answer

Redox reaction

Answer

Neutralization reaction

Answer

Precipitation reaction

Answer

Combustion reaction

Question 10

How is the efficiency of an electrochemical process expressed?

Accepted Answer

Actual yield divided by theoretical yield

Answer

Theoretical yield divided by actual yield

Answer

Cell potential divided by standard cell potential

Answer

Current efficiency divided by voltage efficiency

Question 11

Which of the following statements about redox reactions is accurate?

Accepted Answer

All of the above are true.

Answer

Redox reactions involve the transfer of electrons.

Answer

Oxidation and reduction occur simultaneously.

Answer

The oxidizing agent gains electrons while the reducing agent loses electrons.

Question 12

What is the accepted value for the standard electrode potential of a hydrogen electrode?

Accepted Answer

0 V

Answer

1 V

Answer

1.23 V

Answer

-0.414 V

Question 13

Identify the type of electrochemical cell that is known as a galvanic cell.

Accepted Answer

A cell that generates an electric current spontaneously.

Answer

A cell with a positive cell potential.

Answer

A cell that requires external energy input to drive a chemical reaction.

Answer

A cell that employs negative electrodes.

Question 14

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

Accepted Answer

To maintain electrical neutrality within the cell.

Answer

To facilitate electron flow between half-cells.

Answer

To minimize mixing of solutions in the half-cells.

Answer

To serve as an external energy source.

Question 15

Which factors are known to influence the rate of electrochemical reactions?

Accepted Answer

All of the listed factors.

Answer

Surface area of the electrodes

Answer

Temperature

Answer

Concentration of reactants

Question 16

What is the primary purpose of the Nernst equation?

Accepted Answer

To determine the cell potential of an electrochemical cell under conditions that deviate from the standard state.

Answer

To calculate the equilibrium constant of a given redox reaction.

Answer

To predict the spontaneity of an electrochemical reaction.

Answer

To measure the rate of an electrochemical reaction.

Question 17

What is the primary purpose of a reference electrode?

Accepted Answer

To establish a consistent and reproducible point of reference for cell potential measurements.

Answer

To produce a continuous current.

Answer

To act as an oxidizing agent.

Answer

To prevent unwanted side reactions.

Question 18

In an electrochemical cell, what is the primary function of a salt bridge, and what materials are commonly used in its construction?

Accepted Answer

To maintain electrical neutrality and facilitate ion flow between the half-cells.

Answer

To prevent solution mixing and maintain concentration differences.

Answer

To supply electrons to the cathode.

Answer

To serve as a reference for measuring electrode potentials.

Question 19

Which of the following reactions represents a redox reaction?

Accepted Answer

2H+ + 2e- → H2

Answer

CaCO3 → CaO + CO2

Answer

AgNO3 + NaCl → AgCl + NaNO3

Answer

NaOH + HCl → NaCl + H2O

Question 20

Identify the half-cell reaction for the reduction of oxygen:

Accepted Answer

1/2 O2 + 2H+ + 2e- → H2O

Answer

Zn → Zn2+ + 2e-

Answer

Fe2+ → Fe3+ + e-

Answer

Cu2+ + 2e- → Cu

Question 21

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

Accepted Answer

Maintain electrical neutrality

Answer

Separate the solutions

Answer

Increase the cell's voltage

Answer

Decrease the cell's resistance

Question 22

In an electrochemical cell, which electrode has a negative charge?

Accepted Answer

Cathode

Answer

Anode

Answer

Both anode and cathode

Answer

Neither anode nor cathode

Question 23

The standard reduction potential of a half-reaction primarily measures the:

Accepted Answer

Propensity of the species to undergo reduction

Answer

Propensity of the species to undergo oxidation

Answer

Difference in free energy between reactants and products

Answer

Equilibrium constant of the half-reaction

Question 24

The Nernst equation is primarily employed for calculating the:

Accepted Answer

Cell potential under non-standard conditions

Answer

Equilibrium constant of a redox reaction

Answer

Gibbs free energy change of a redox reaction

Answer

Standard reduction potential of a half-reaction

Question 25

The oxidation number of carbon in CO2 is:

Accepted Answer

+4

Answer

-4

Answer

+2

Answer

-2

Question 26

Identify the species that acts as a reducing agent:

Accepted Answer

Fe2+

Answer

MnO4-

Answer

Cr2O72-

Answer

Br2

Question 27

The electrolysis of water primarily produces:

Accepted Answer

Hydrogen and oxygen

Answer

Hydrogen and chlorine

Answer

Oxygen and chlorine

Answer

Hydrogen and bromine

Question 28

The efficiency of an electrochemical cell is defined as:

Accepted Answer

Ratio of actual work done to theoretical work

Answer

Ratio of theoretical work done to actual work

Answer

Ratio of cell potential to standard cell potential

Answer

Ratio of current to voltage

Question 29

Identify the redox reaction among the following:

Accepted Answer

2Na + 2H2O → 2NaOH + H2

Answer

NaCl + AgNO3 → AgCl + NaNO3

Answer

HCl + NaOH → NaCl + H2O

Answer

CH4 + 2O2 → CO2 + 2H2O

Question 30

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

Accepted Answer

0 V

Answer

1 V

Answer

0.5 V

Answer

-1 V

Question 31

Which of the following describes a galvanic cell?

Accepted Answer

A cell that generates electrical energy from a spontaneous chemical reaction

Answer

A cell that requires electrical energy to drive a non-spontaneous chemical reaction

Answer

A cell that utilizes electrodes made of the same material

Question 32

What is the primary purpose of the Nernst equation?

Accepted Answer

To calculate the cell potential of an electrochemical cell under non-standard conditions

Answer

To calculate the standard reduction potential of a half-reaction

Answer

To determine the equilibrium constant of a redox reaction

Question 33

Define titration:

Accepted Answer

A technique that involves adding a solution of known concentration to a solution of unknown concentration

Answer

A method for measuring the pH of a solution

Answer

A process used to determine the melting point of a solid

Question 34

In a titration, what does the equivalence point represent?

Accepted Answer

The point at which the moles of titrant added are equivalent to the moles of analyte present

Answer

The point at which the pH of the solution becomes neutral

Question 35

Which of the following is a potentiometric sensor?

Accepted Answer

A device that measures the potential difference between two electrodes

Answer

A device that measures gas concentration

Answer

A device that measures temperature

Question 36

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

Accepted Answer

To maintain the electrical neutrality of the cell

Answer

To prevent the mixing of solutions

Answer

To serve as a reference electrode

Answer

To enhance the conductivity of the cell

Question 37

Which of the following describes a fuel cell?

Accepted Answer

A device that converts the chemical energy of a fuel into electrical energy

Answer

A device that measures gas concentration

Answer

A device that converts electrical energy into chemical energy

Question 38

Which of the following processes involves the transfer of electrons from one species to another?

Accepted Answer

Oxidation-Reduction (Redox)

Answer

Neutralization

Answer

Sublimation

Answer

Ionization

Question 39

In an electrochemical cell, the electrode where oxidation occurs is called the:

Accepted Answer

Anode

Answer

Electrolyte

Answer

Cathode

Answer

Salt bridge

Question 40

The potential of the standard hydrogen electrode (SHE) is defined as:

Accepted Answer

0.00 V

Answer

-1.00 V

Answer

0.70 V

Answer

1.00 V

Question 41

Which of the following applications utilizes potentiometry to determine the concentration of ions in solution?

Accepted Answer

pH measurement

Answer

Electrophoresis

Answer

Electroplating

Answer

Battery charging

Question 42

The Nernst equation expresses the relationship between the cell potential (E) and the:

Accepted Answer

Concentration of reactants and products

Answer

Temperature and pressure

Answer

Surface area of electrodes

Answer

Resistance of the circuit

Question 43

An electrochemical sensor that selectively responds to and measures the concentration of specific ions in solution is known as a(n):

Accepted Answer

Ion-selective electrode (ISE)

Answer

Thermistor

Answer

Piezoelectric sensor

Answer

Hall effect sensor

Question 44

In the process of electroplating, a metal is deposited on a surface through:

Accepted Answer

Reduction of metal ions

Answer

Electrolysis of water

Answer

Ion exchange

Answer

Oxidation of metal atoms

Question 45

Fuel cells produce electricity by harnessing the chemical energy stored in:

Accepted Answer

Redox reactions

Answer

Mechanical energy

Answer

Solar energy

Answer

Nuclear reactions

Question 46

Corrosion, a process that deteriorates metal surfaces, is primarily caused by:

Accepted Answer

Electrochemical oxidation

Answer

Thermal decomposition

Answer

Biofouling

Answer

Mechanical abrasion

Question 47

Which of the following is the **standard reduction potential** for the standard hydrogen electrode?

Accepted Answer

0 V

Answer

-1 V

Answer

0.5 V

Answer

1 V

Question 48

In a galvanic cell, **oxidation** occurs at the:

Accepted Answer

Anode

Answer

Cathode

Answer

Salt bridge

Question 49

The process of coating a metal with another metal by electrolysis is called:

Accepted Answer

Electroplating

Answer

Electrolysis

Answer

Electrophoresis

Answer

Galvanization

Question 50

Which of the following is a **limitation** of using potentiometric sensors?

Accepted Answer

Interference from other ions

Answer

High sensitivity

Answer

Fast response time

Answer

Wide dynamic range

Question 51

Which of the following is a common **application** of coulometry?

Accepted Answer

Determining the amount of a substance in a solution

Answer

Analyzing the composition of a gas sample

Answer

Measuring the pH of a solution

Question 52

The process of separating ions based on their **size** using an electric field is called:

Accepted Answer

Electrophoresis

Answer

Chromatography

Answer

Spectrophotometry

Answer

Electrolysis