Electrochemical Methods: Master the Fundamentals of Electroanalytical Techniques

Question 1

In cyclic voltammetry, which parameter controls the rate at which the potential is scanned?

Accepted Answer

Scan rate

Answer

Scan amplitude

Answer

Sweep width

Answer

Voltage range

Question 2

Which of the following is not an advantage of potentiometric methods?

Accepted Answer

Ability to analyze mixtures with multiple components

Answer

Direct measurement of ion concentration

Answer

High sensitivity and selectivity

Answer

Simplicity and low cost

Question 3

Electroanalysis finds applications in various fields. Which of the following is NOT a common application?

Accepted Answer

Analysis of archaeological artifacts

Answer

Drug analysis in the pharmaceutical industry

Answer

Environmental monitoring

Answer

Biomolecule detection

Question 4

The Nernst equation describes the relationship between:

Accepted Answer

Cell potential and ion concentration

Answer

Current and potential

Answer

Capacitance and voltage

Answer

Inductance and frequency

Question 5

Refined: What underlies the fundamental principle of potentiometric measurements?

Accepted Answer

Nernst equation

Answer

Arrhenius equation

Answer

Einstein's equation

Answer

Schrödinger equation

Question 6

Specified: Which factor primarily influences the characteristic shape of a cyclic voltammogram?

Accepted Answer

Scan rate only

Answer

Electrode geometry only

Answer

Solution composition only

Answer

Temperature only

Question 7

Clarified: What is the main purpose of a salt bridge in electrochemical cells?

Accepted Answer

Maintain electrical contact between half-cells

Answer

Prevent contamination

Answer

Introduce a redox mediator

Answer

Buffer the solution

Question 8

Simplified: Which type of electrode reaction involves an exchange of electrons?

Accepted Answer

Redox reaction

Answer

Precipitation reaction

Answer

Acid-base reaction

Answer

Photochemical reaction

Question 9

Corrected: In potentiometry, the measured potential difference is directly proportional to:

Accepted Answer

Activity

Answer

Density

Answer

Concentration

Answer

Molarity

Question 10

What is the fundamental principle underlying the functioning of cyclic voltammetry?

Accepted Answer

Linear sweep of potential while measuring the resultant current

Answer

Stepwise application of potential followed by current measurement

Answer

Oscillating potential while measuring current

Answer

Constant potential with continuous current measurement

Question 11

Which of the following factors does NOT influence the peak current observed in cyclic voltammetry?

Accepted Answer

Pressure of the solution

Answer

Scan rate

Answer

Concentration of analyte

Answer

Temperature

Question 12

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

Accepted Answer

To provide a stable and fixed potential reference

Answer

To generate the working potential

Answer

To measure the current flowing through the cell

Answer

To act as a counter electrode

Question 13

Which electrochemical technique relies on measuring electrical conductivity to determine the concentration of an unknown solution?

Accepted Answer

Conductometry

Answer

Potentiometry

Answer

Voltammetry

Answer

Amperometry

Question 14

What is the key distinction between a potentiometric sensor and a voltammetric sensor?

Accepted Answer

Potentiometric sensors measure potential, while voltammetric sensors measure current

Answer

Voltammetric sensors measure potential, while potentiometric sensors measure current

Answer

Both potentiometric and voltammetric sensors measure potential

Answer

Both potentiometric and voltammetric sensors measure current

Question 15

Which factor does **NOT** affect the rate of an electrochemical reaction?

Accepted Answer

Pressure

Answer

Concentration of reactants

Answer

Temperature

Answer

Surface area of the electrode

Question 16

What is the relationship between the cell potential (E) and the standard reduction potentials of the half-reactions?

Accepted Answer

E = E°cell = E°red - E°oxid

Answer

E = E°red / E°oxid

Answer

E = E°cell = E°oxid + E°red

Answer

E = E°cell / (E°red * E°oxid)

Question 17

Which of the following factors can affect the rate of an electrochemical reaction?

Accepted Answer

Concentration of reactants and products, temperature, surface area of electrodes

Answer

Only temperature and surface area of electrodes

Answer

Only concentration of reactants

Question 18

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

Accepted Answer

To provide a stable and reproducible potential

Answer

To measure the cell current

Answer

To act as the cathode

Answer

To control the flow of electrons

Question 19

Which of the following techniques is primarily used to study the kinetics of electrochemical reactions?

Accepted Answer

Cyclic voltammetry

Answer

Conductometry

Answer

Spectrophotometry

Answer

Potentiometry

Question 20

What is the key difference between a potentiostat and a galvanostat?

Accepted Answer

A potentiostat controls the cell potential, while a galvanostat controls the cell current

Answer

Both potentiostats and galvanostats control the cell potential and current

Answer

A potentiostat controls the cell current, while a galvanostat controls the cell potential

Question 21

Which of the following applications of electrochemical methods is primarily utilized in the medical field?

Accepted Answer

Electrocardiography (ECG)

Answer

Water purification

Answer

Electroplating

Answer

Battery manufacturing

Question 22

What is the Nernst equation primarily used to calculate?

Accepted Answer

The cell potential based on the concentrations of reactants and products

Answer

The cell current based on the cell potential

Answer

The rate of an electrochemical reaction based on the cell potential

Question 23

Which of the following is a potential limitation of electrochemical methods?

Accepted Answer

Susceptibility to interferences and requirement for specialized equipment

Answer

Applicable to all types of analytes

Answer

Always provide highly accurate and precise results

Question 24

What is the primary role of a supporting electrolyte in an electrochemical cell?

Accepted Answer

To enhance conductivity and minimize resistance

Answer

To prevent unwanted side reactions

Answer

To serve as the reactant or product