Analytical Chemistry: Principles and Applications for Year 12

Question 1

What is the primary role of the internal standard in quantitative analysis?

Accepted Answer

To correct for variations in sample preparation

Answer

To calibrate the instrument

Answer

To identify the components of a mixture

Answer

To enhance the sensitivity of the analysis

Question 2

Which of the following is an example of an application of analytical chemistry in medicine?

Accepted Answer

Blood glucose monitoring

Answer

Environmental monitoring

Answer

Forensic science

Answer

Materials characterization

Question 3

What is the primary purpose of using a blank solution in an analytical procedure?

Accepted Answer

To correct for background interference

Answer

To calibrate the instrument

Answer

To determine the concentration of the analyte

Answer

To enhance the sensitivity of the analysis

Question 4

Which type of chromatography is specifically designed for separating charged molecules?

Accepted Answer

Ion exchange chromatography

Answer

Gas chromatography

Answer

Liquid chromatography

Answer

Size exclusion chromatography

Question 5

What is the relationship between the wavelength of light absorbed and the energy difference between two electronic states in a molecule?

Accepted Answer

The shorter the wavelength, the higher the energy difference

Answer

The longer the wavelength, the higher the energy difference

Answer

The wavelength is independent of the energy difference

Answer

The wavelength is inversely proportional to the energy difference

Question 6

Which analytical technique separates and identifies organic compounds based on their different boiling points?

Accepted Answer

Chromatography

Answer

Spectroscopy

Answer

Electrochemistry

Answer

Thermal analysis

Question 7

In infrared spectroscopy, which type of radiation is utilized?

Accepted Answer

Infrared radiation

Answer

X-rays

Answer

Ultraviolet radiation

Answer

Visible light

Question 8

In analytical chemistry, what calibration method compares the measured response of an unknown solution to that of known standards to determine its concentration?

Accepted Answer

External standard method

Answer

Standard addition method

Answer

Internal standard method

Answer

Blank method

Question 9

According to Beer's Law, how is the absorbance of a solution related to its concentration and the path length of the light beam?

Accepted Answer

The absorbance is directly proportional to both concentration and path length

Answer

The absorbance is inversely proportional to concentration

Answer

The absorbance is directly proportional to the logarithm of concentration

Answer

The absorbance is independent of path length

Question 10

In electrochemical measurements, what function does a reference electrode serve?

Accepted Answer

It provides a stable potential reference

Answer

It conducts the current

Answer

It detects the analyte

Answer

It amplifies the signal

Question 11

What technique is used to separate a mixture of liquids based on their different boiling points?

Accepted Answer

Distillation

Answer

Chromatography

Answer

Titration

Answer

Spectroscopy

Question 12

What is the primary function of a primary standard in volumetric analysis?

Accepted Answer

To calibrate the measuring equipment

Answer

To react with the analyte

Answer

To determine the concentration of the analyte directly

Answer

To act as a buffer

Question 13

Which of the following techniques is used for qualitative analysis?

Accepted Answer

Flame test

Answer

Titration

Answer

Gas chromatography - mass spectrometry (GC-MS)

Answer

Atomic absorption spectroscopy (AAS)

Question 14

Which of the following is NOT a spectroscopic technique used in analytical chemistry?

Accepted Answer

Gas chromatography

Answer

Atomic absorption spectroscopy

Answer

Infrared spectroscopy

Answer

Nuclear magnetic resonance spectroscopy

Question 15

Which chromatographic technique is most suitable for separating non-volatile liquids?

Accepted Answer

High-performance liquid chromatography (HPLC)

Answer

Gas chromatography

Answer

Thin-layer chromatography (TLC)

Answer

Paper chromatography

Question 16

The oxidation state of the central metal ion in the complex ion hexacyanoferrate(IV), [Fe(CN)6]^4-, is:

Accepted Answer

+4

Answer

+2

Answer

+3

Answer

+6

Question 17

Molar absorptivity is defined as:

Accepted Answer

The absorbance of a solution divided by its concentration and path length

Answer

The concentration of a solution divided by its absorbance and path length

Answer

The path length of a solution divided by its absorbance and concentration

Answer

The absorbance of a solution multiplied by its concentration and path length

Question 18

Which of the following is a characteristic of a strong electrolyte?

Accepted Answer

Dissociates completely in solution

Answer

Has a low conductivity in solution

Answer

Is a nonpolar molecule

Answer

Forms a weak intermolecular bond

Question 19

The pH of a solution is primarily determined by:

Accepted Answer

The concentration of hydrogen ions in solution

Answer

The concentration of hydroxide ions in solution

Answer

The temperature of the solution

Answer

The molarity of the solution

Question 20

The rate law for a chemical reaction is an equation that expresses:

Accepted Answer

The relationship between the rate of the reaction and the concentrations of the reactants

Answer

The equilibrium constant for the reaction

Answer

The activation energy for the reaction

Answer

The half-life of the reaction

Question 21

Which of the following is NOT a spectroscopic technique used in analytical chemistry?

Accepted Answer

Gas chromatography

Answer

Atomic emission spectrometry

Answer

Molecular absorption spectrometry

Answer

Mass spectrometry

Question 22

Which of the following is an electrochemical technique used in analytical chemistry?

Accepted Answer

Potentiometry

Answer

Atomic absorption spectrometry

Answer

Gas chromatography

Answer

Nuclear magnetic resonance spectroscopy

Question 23

What is the primary role of a buffer solution in potentiometric titrations?

Accepted Answer

To maintain a relatively constant pH during the titration

Answer

To enhance the conductivity of the solution

Answer

To reduce the rate of the reaction

Answer

To neutralize the titrant

Question 24

What is the primary purpose of constructing a calibration curve in spectrophotometry?

Accepted Answer

To determine the concentration of an unknown sample

Answer

To identify the compound present in a sample

Answer

To calculate the molar absorptivity of a compound

Answer

To calibrate the spectrophotometer

Question 25

What is the fundamental difference between qualitative and quantitative analysis?

Accepted Answer

Qualitative analysis provides information about the presence or absence of a substance, while quantitative analysis provides information about the amount of a substance

Answer

Qualitative analysis is more accurate than quantitative analysis

Answer

Quantitative analysis is more time-consuming than qualitative analysis

Answer

There is no distinction between qualitative and quantitative analysis

Question 26

To measure the pH of a solution, which instrument is most appropriate?

Accepted Answer

pH meter

Answer

Conductivity meter

Answer

Spectrophotometer

Answer

Burette

Question 27

Accuracy in an analytical method refers to:

Accepted Answer

The closeness of the measured value to the true value

Answer

The consistency of repeated measurements

Answer

The sensitivity of the method

Answer

The ease of performing the method

Question 28

The limit of detection in an analytical method is defined as:

Accepted Answer

The lowest detectable concentration of an analyte with certainty

Answer

The highest measurable concentration of an analyte with accuracy

Answer

The standard deviation of measured values

Answer

The gradient of the calibration curve

Question 29

Which chromatographic technique separates a mixture of substances based on their boiling points?

Accepted Answer

Gas chromatography

Answer

High-performance liquid chromatography

Answer

Thin-layer chromatography

Answer

Paper chromatography

Question 30

Which of the following is a quantitative analytical technique employed to determine the concentration of a substance in a sample?

Accepted Answer

Atomic absorption spectroscopy

Answer

Thin-layer chromatography

Answer

Gel electrophoresis

Answer

Paper chromatography

Question 31

What is the primary function of a buffer solution in analytical chemistry?

Accepted Answer

To maintain a constant pH in a solution

Answer

To increase the solubility of a substance

Answer

To act as a reducing agent

Answer

To enhance the conductivity of a solution

Question 32

Which of the following is a widely used type of chemical sensor that measures the concentration of ions in a solution?

Accepted Answer

pH electrode

Answer

Biosensor

Answer

Conductivity probe

Answer

Electrochemical cell

Question 33

What is the fundamental principle behind the separation of components in a gas chromatograph?

Accepted Answer

Separation based on boiling point differences

Answer

Separation based on solubility differences

Answer

Separation based on charge differences

Answer

Separation based on size differences

Question 34

Which spectroscopic technique relies on the absorption of electromagnetic radiation in the ultraviolet and visible regions to identify and characterize organic compounds?

Accepted Answer

UV-Vis spectroscopy

Answer

Infrared spectroscopy

Answer

Atomic absorption spectroscopy

Answer

Nuclear magnetic resonance spectroscopy

Question 35

Chromatographic techniques separate components of a mixture primarily based on their:

Accepted Answer

Differential distribution between a stationary and a mobile phase

Answer

Molecular weights

Answer

Boiling points

Question 36

Which of the following techniques does NOT belong to the category of electrochemical analysis?

Accepted Answer

Gas chromatography

Answer

Conductometry

Answer

Potentiometry

Answer

Voltammetry

Question 37

The process of transforming an analyte into a more suitable form for detection and quantification is known as:

Accepted Answer

Sample preparation

Answer

Titration

Answer

Chromatography

Answer

Calibration

Question 38

Accuracy in analytical chemistry refers to the:

Accepted Answer

Closeness of the measured value to the true value

Answer

Specificity of the method

Answer

Precision of the measured values

Answer

Sensitivity of the method

Question 39

The limit of detection (LOD) of an analytical method is defined as the:

Accepted Answer

Lowest concentration of analyte that can be reliably detected

Answer

Concentration of analyte that gives a signal twice the background noise

Answer

Highest concentration of analyte that can be measured accurately

Question 40

Which spectroscopic technique is most effective for identifying the functional groups present in organic molecules?

Accepted Answer

Infrared (IR) spectroscopy

Answer

Ultraviolet-Visible (UV-Vis) spectroscopy

Answer

Mass spectrometry (MS)

Answer

Nuclear Magnetic Resonance (NMR) spectroscopy

Question 41

A calibration curve in analytical chemistry is used to:

Accepted Answer

Relate instrument response to analyte concentration.

Answer

Determine the purity of a sample.

Answer

Compare the results of different analytical techniques.

Answer

Calculate the reaction rate of a chemical process.

Question 42

Which of these is NOT a primary factor to consider when choosing an analytical technique?

Accepted Answer

Cost of the equipment.

Answer

Sensitivity of the technique.

Answer

Accuracy and precision of the technique.

Answer

Specificity of the technique.

Question 43

A sample is analyzed using UV-Vis spectroscopy, and its absorbance spectrum shows a peak at 520 nm. What can be concluded about the sample?

Accepted Answer

The sample absorbs light at 520 nm.

Answer

The sample is colorless.

Answer

The sample contains a specific functional group.

Answer

The sample emits light at 520 nm.

Question 44

A standard solution is a solution with a known:

Accepted Answer

Concentration.

Answer

Density.

Answer

Mass.

Answer

Volume.