Electroanalytical Chemistry Quizzes: Test Your Knowledge

Question 1

What is the primary purpose of a reference electrode in an electrochemical cell?

Accepted Answer

Establish a stable and well-defined reference potential

Answer

Measure the potential difference between the working and counter electrodes

Answer

Provide a source of electrons for the electrochemical reaction

Answer

Amplify the signal generated by the working electrode

Question 2

What is the primary application of the Nernst equation in electrochemistry?

Accepted Answer

Calculating the potential of an electrochemical cell under specified conditions

Answer

Determining the concentration of an analyte in a solution

Answer

Predicting the products formed in an electrochemical reaction

Answer

Measuring the rate of an electrochemical reaction

Question 3

In amperometry, how is the concentration of an analyte determined?

Accepted Answer

Measuring the current flowing through a solution at a fixed potential

Answer

Measuring the potential difference between electrodes

Answer

Measuring the conductivity of a solution

Answer

Measuring the current flowing through a solution as the potential is varied

Question 4

Which of the following is NOT an electrochemical method used in analytical chemistry?

Accepted Answer

Chromatography

Answer

Potentiometry

Answer

Voltammetry

Answer

Amperometry

Question 5

In amperometry, the current flowing through the cell is directly proportional to the:

Accepted Answer

Concentration of the analyte

Answer

Applied potential

Answer

Resistance of the solution

Answer

Temperature of the solution

Question 6

In electroanalytical chemistry, which technique involves measuring changes in cell potential to determine the concentration of an analyte?

Accepted Answer

Potentiometry

Answer

Voltammetry

Answer

Amperometry

Answer

Conductometry

Question 7

What is the fundamental difference between potentiometry and voltammetry?

Accepted Answer

Potentiometry measures cell potential, while voltammetry measures current

Answer

Potentiometry measures current, while voltammetry measures cell potential

Answer

Both techniques measure cell potential

Answer

Both techniques measure current

Question 8

Which electrode is used to establish a stable reference potential in a potentiometric electrochemical cell?

Accepted Answer

Reference electrode

Answer

Working electrode

Answer

Counter electrode

Answer

Glass electrode

Question 9

What is the primary function of the Nernst equation in electrochemistry?

Accepted Answer

Calculating the potential of an electrochemical cell

Answer

Calculating the concentration of an analyte

Answer

Determining the pH of a solution

Answer

Measuring the conductivity of a solution

Question 10

Which of the following is an application of amperometry?

Accepted Answer

Measuring dissolved oxygen concentration

Answer

Measuring pH of a solution

Answer

Titrating a solution

Answer

Measuring conductivity of a solution

Question 11

Which of the following methods is NOT included in electroanalytical chemistry as discussed in Unit 3.4?

Accepted Answer

Spectrophotometry

Answer

Potentiometry

Answer

Voltammetry

Answer

Amperometry

Question 12

Define the principle of potentiometry.

Accepted Answer

Measuring the voltage difference between two electrodes.

Answer

Measuring the current flowing between two electrodes.

Answer

Measuring the resistance between two electrodes.

Answer

Measuring the capacitance between two electrodes.

Question 13

In amperometry, how does the concentration of the analyte relate to the current measured?

Accepted Answer

Linearly proportional.

Answer

Exponentially proportional.

Answer

Inversely proportional.

Answer

Logarithmically proportional.

Question 14

Describe the significance of the Nernst equation in electroanalytical chemistry.

Accepted Answer

It relates the cell potential to the concentration of the analyte.

Answer

It predicts the spontaneity of a reaction.

Answer

It determines the equilibrium constant.

Answer

It calculates the standard reduction potential.

Question 15

Which electrochemical technique is best suited for real-time monitoring of chemical processes?

Accepted Answer

Chronoamperometry

Answer

Cyclic voltammetry

Answer

Polarography

Answer

Coulometry

Question 16

What is the fundamental principle behind potentiometry?

Accepted Answer

Measuring the potential difference between two electrodes

Answer

Applying a potential to drive a reaction

Answer

Measuring the current produced by a reaction

Answer

Detecting the presence of a specific ion

Question 17

What is the primary purpose of the Nernst equation?

Accepted Answer

Calculating the potential of an electrochemical cell

Answer

Determining the concentration of a solution

Answer

Predicting the direction of a reaction

Answer

Calibrating electrochemical instruments

Question 18

What differentiates a cyclic voltammogram from a linear sweep voltammogram?

Accepted Answer

Cyclic voltammetry involves bi-directional potential scanning, while linear sweep voltammetry scans in only one direction.

Answer

Cyclic voltammetry measures current versus potential, while linear sweep voltammetry measures potential versus current.

Answer

Cyclic voltammetry studies electrode kinetics, while linear sweep voltammetry determines electron transfer count in reactions.

Answer

These techniques exhibit no differences.

Question 19

Explain the principle behind amperometry.

Accepted Answer

Measuring current flow through a solution at a constant potential.

Answer

Measuring solution potential at a constant current.

Answer

Measuring electrochemical reaction rate by monitoring electrode mass change.

Answer

Measuring solution conductivity.

Question 20

Describe the function of a reference electrode in electroanalytical chemistry.

Accepted Answer

Provides a stable and known potential for comparison against other electrodes.

Answer

Generates current to drive electrochemical reactions.

Answer

Consumes electrons from solution to balance reactions.

Answer

Amplifies signals from the working electrode.

Question 21

What is the Nernst equation used to calculate?

Accepted Answer

Cell potential

Answer

Current

Answer

Resistance

Answer

Capacitance

Question 22

What is the difference between a working electrode and a reference electrode?

Accepted Answer

The working electrode is used for the reaction of interest, while the reference electrode provides a stable potential.

Answer

The reference electrode is used for the reaction of interest, while the working electrode provides a stable potential.

Answer

Both electrodes serve the same purpose.

Answer

There is no difference between a working electrode and a reference electrode.

Question 23

What is the difference between coulometry and amperometry?

Accepted Answer

Coulometry measures the total charge passed through the cell, while amperometry measures the current flowing through the cell.

Answer

Amperometry measures the total charge passed through the cell, while coulometry measures the current flowing through the cell.

Answer

Both techniques measure the same thing.

Answer

There is no difference between coulometry and amperometry.

Question 24

The Nernst equation is primarily used to calculate:

Accepted Answer

Cell potential of an electrochemical cell

Answer

Concentration of an analyte

Answer

Current flowing through an electrochemical cell

Answer

Products of an electrochemical reaction

Question 25

Which electroanalytical technique directly measures the concentration of an analyte by measuring the current flowing through an electrochemical cell?

Accepted Answer

Amperometry

Answer

Potentiometry

Answer

Voltammetry

Answer

Conductometry

Question 26

What is the primary distinction between a working electrode and a reference electrode?

Accepted Answer

The working electrode hosts the electrochemical reaction, while the reference electrode provides a stable reference potential.

Answer

The reference electrode hosts the electrochemical reaction, while the working electrode provides a stable reference potential.

Answer

Both the working electrode and reference electrode provide stable reference potentials.

Answer

Both the working electrode and reference electrode host electrochemical reactions.

Question 27

The fundamental difference between a potentiometric sensor and an amperometric sensor lies in their measurement principles:

Accepted Answer

Potentiometric sensors measure cell potential, while amperometric sensors measure current.

Answer

Amperometric sensors measure cell potential, while potentiometric sensors measure current.

Answer

Both potentiometric and amperometric sensors measure cell potential.

Answer

Both potentiometric and amperometric sensors measure current.

Question 28

Which of the following is NOT an electrochemical method commonly used in analytical chemistry?

Accepted Answer

Colorimetry

Answer

Potentiometry

Answer

Voltammetry

Answer

Amperometry

Question 29

The Nernst equation relates the measured potential difference in an electrochemical cell to:

Accepted Answer

Temperature and the concentrations of reactants and products

Answer

Electrical current flowing through the cell and time

Answer

Mass and volume of the reactants

Answer

pH and ionic strength of the solution

Question 30

In cyclic voltammetry, the potential applied to the working electrode is:

Accepted Answer

Varied linearly, first in the positive and then in the negative direction

Answer

Kept constant at a specific value

Answer

Increased randomly within a certain range

Answer

Decreased exponentially with time

Question 31

Which type of electrode serves as the reference electrode in a potentiometric cell?

Accepted Answer

Calomel electrode

Answer

Glass electrode

Answer

Working electrode

Answer

Counter electrode

Question 32

Amperometry is primarily used to measure:

Accepted Answer

Electrical current flowing through the cell

Answer

Potential difference between the electrodes

Answer

Mass change of the working electrode

Answer

Temperature change of the solution

Question 33

In a voltaic cell, the spontaneous flow of electrons is from the:

Accepted Answer

Anode to the cathode

Answer

Cathode to the anode

Answer

Reference electrode to the working electrode

Answer

Counter electrode to the auxiliary electrode

Question 34

Anodic stripping voltammetry involves:

Accepted Answer

Depositing the analyte onto the electrode surface and then stripping it off

Answer

Reacting the analyte with a supporting electrolyte

Answer

Oxidizing the analyte in solution

Answer

Reducing the analyte at the cathode

Question 35

In amperometry, the current measured is directly proportional to:

Accepted Answer

Concentration of the analyte

Answer

Applied potential

Answer

Temperature

Answer

Surface area of the electrode

Question 36

Which of the following electrodes is commonly used as a reference electrode in potentiometry?

Accepted Answer

Calomel electrode

Answer

Glass electrode

Answer

Platinum electrode

Answer

Carbon electrode

Question 37

Which type of electrochemical cell is specifically designed to measure the concentration of an analyte?

Accepted Answer

Concentration cell

Answer

Galvanic cell

Answer

Electrolytic cell

Answer

Reference cell

Question 38

Potentiometry relies on which fundamental principle?

Accepted Answer

Measuring the difference in electrical potential

Answer

Measuring the flow of current

Answer

Measuring changes in mass

Answer

Measuring the conductivity of a solution

Question 39

What is the primary purpose of the Nernst equation in electrochemistry?

Accepted Answer

Calculating the potential of an electrochemical cell

Answer

Determining the concentration of an analyte

Answer

Calculating the current flowing through an electrochemical cell

Answer

Calculating the resistance of an electrochemical cell

Question 40

Which electroanalytical technique is most suitable for determining the number of electrons involved in a redox reaction?

Accepted Answer

Cyclic voltammetry

Answer

Linear sweep voltammetry

Answer

Amperometry

Answer

Potentiometry

Question 41

Which of the following techniques is primarily used for measuring the current flowing through an electrochemical cell?
(A) Potentiometry
(B) Voltammetry
(C) Amperometry
(D) Conductimetry

Accepted Answer

C. Amperometry

Answer

A. Potentiometry

Answer

B. Voltammetry

Answer

D. Conductimetry

Question 42

Which of the following factors can influence the rate of an electrochemical reaction?
(A) Temperature
(B) Concentration of reactants
(C) Surface area of the electrode
(D) All of the above

Accepted Answer

D. All of the above

Answer

A. Temperature

Answer

B. Concentration of reactants

Answer

C. Surface area of the electrode