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Mock Gen Chem
100問 • 3ヶ月前
  • Liane
  • 通報

    問題一覧

  • 1

    What is 2.34 × 10^5 written in standard decimal form?

    234000

  • 2

    How many significant figures are there in the measurement 3.400 g?

    4

  • 3

    Express the number 0.051065 to four significant figures.

    0.05107

  • 4

    A prediction or possible explanation for a question or problem that can be tested in an experiment is called:

    Hypothesis

  • 5

    Which of the following is best described as having components that can be physically separated?

    Mixture

  • 6

    Which of the following is an extensive property of matter?

    Neither — both density and viscosity are intensive properties

  • 7

    Mass is best defined as:

    The amount of matter in an object

  • 8

    Which of the following will cause the mass of a metal block to increase?

    None of the above

  • 9

    Liquid A has a lower boiling point than liquid B. Which best describes the boiling point of a solution made by mixing A and B?

    Between the boiling points of A and B

  • 10

    Which of the following does NOT indicate that a chemical change has occurred?

    Change in shape

  • 11

    What happens when two materials with different densities, such as oil and water, come into contact?

    Separate based on their densities

  • 12

    Most substances are denser in their solid state than in their liquid state. However, water is unique because:

    Its solid form is less dense than its liquid form.

  • 13

    Determine the actual volume contained in a 50.0 mL volumetric flask given the following data. Mass of water: 50.1227 g. Density of water at 25°C: 0.99707 g/mL.

    50.27 mL

  • 14

    According to the kinetic molecular theory, gas particles are in:

    Continuous random motion

  • 15

    Which of the following assumptions is part of the kinetic molecular theory?

    Gas particles have negligible volume compared to the container.

  • 16

    What is the molar mass of an unknown gas if 1.60 g of the gas occupies a volume of 2.24 L at STP (273.15 K and 1 bar)? (1 atm = 1.01325 bar)

    16.2 g/mol

  • 17

    Which of the following gases behaves most like an ideal gas under standard conditions?

    Helium (He)

  • 18

    Three flasks (labeled 1, 2, 3) each contain the same number of gas molecules at the same temperature. In which flask is the pressure highest?

    The flask with the smallest volume

  • 19

    When water is heated in a beaker, bubbles of air form on the side of the glass before the water begins to boil. This observation indicates that the solubility of gases in water:

    Decreases as temperature increases

  • 20

    Which of the following is true for the C-12 isotope?

    It has 6 protons and 6 neutrons.

  • 21

    Noble gases are chemically inert because they have complete outer electron shells. Which of the following elements is not a noble gas?

    Chlorine

  • 22

    Sodium carbonate is commonly known as:

    Soda ash

  • 23

    Which name does not correctly refer to Hg2Cl2?

    Mercury(II) chloride

  • 24

    Which of the following statements does not describe a nonpolar covalent bond?

    It is a bond between different nonmetal atoms.

  • 25

    When 7 g of carbon reacts completely with 4 g of oxygen, what is the total mass of the product formed?

    11 g

  • 26

    A 1.00 g sample of which compound will produce the highest amount of carbon dioxide after complete combustion with excess oxygen?

    C4H10

  • 27

    The water content of an 875.4 mg sample of cheese was determined using a moisture analyzer. If the final dry mass after analysis is 545.8 mg, what is the % H2O in the cheese?

    37.65%

  • 28

    The substance that does the dissolving and makes up more than 50% of the solution is the:

    Solvent

  • 29

    Which of the following best describes the relationship between viscosity and solubility of a liquid in a solvent?

    Lower viscosity usually results in better solubility due to easier molecular movement

  • 30

    What is the normality of a 5.0 M sulfuric acid solution?

    10.0 N

  • 31

    Which of the following is equivalent to 0.01% by weight?

    100 ppm

  • 32

    A solution has a Cu2+ concentration of 3.0 × 10^-4 M. What is the Cu2+ concentration in parts per million (ppm)? (Molar mass of Cu = 63.55 g/mol)

    19.1 ppm

  • 33

    How many grams of NaOH (40.0 g/mol) are required to prepare 500 mL of 0.500 N NaOH solution? (Assume NaOH is monoprotic so N = M.)

    10.0 g

  • 34

    What is the molarity of a solution prepared by dissolving 72.9 g of HCl (36.46 g/mol) in enough water to make 500 mL of solution?

    4.00 mol/L

  • 35

    A solution of HCl has a molarity of 6.0 M and a density of 1.10 g/mL. Calculate the molality (mol/kg) of the solution. (Molar mass of HCl = 36.46 g/mol)

    6.81 m

  • 36

    What volume of 4.0 M HCl is needed to prepare 1.0 L of a 0.5 M solution?

    0.125 L

  • 37

    A student has three stock solutions: Zn at 2000 ppm, Cd at 1500 ppm, and Pb at 1000 ppm. The student takes 10 mL from each solution and dilutes to 200 mL total. What is the final concentration of each element in the mixture?

    100 ppm Zn, 75 ppm Cd, 50 ppm Pb

  • 38

    Under the Lewis concept of acids and bases, a Lewis acid is a(n):

    Electron pair acceptor

  • 39

    Which of the following substances is basic?

    Milk of magnesia

  • 40

    What is the pH of a 0.10 M NaOH solution?

    13

  • 41

    If the pOH of a solution is 3.5, what is the pH of the solution?

    10.5

  • 42

    Which laboratory test can help distinguish an unknown white solid being NaOH or NH4NO3?

    Aqueous NaOH turns litmus paper blue, while NH4NO3 does not change litmus color.

  • 43

    When chromium changes from an oxidation state of +3 to +6, chromium must:

    Lose 3 electrons

  • 44

    Consider the reaction Mg + 2 H2O → Mg(OH)2 + H2. Which of the following statements is false?

    Mg is the oxidizing agent

  • 45

    In an electrolytic cell, oxidation occurs:

    At the anode

  • 46

    During the electroplating of silver, what happens to the silver ions in solution?

    They are reduced at the cathode to form metallic silver.

  • 47

    An unknown metal nitrate is electrolyzed in water. During the process, X grams of the metal were deposited at the cathode, and simultaneously X grams of copper dissolved into the anolyte solution. Which metal is the most likely identity of the unknown metal?

    Copper (Cu)

  • 48

    A binary liquid mixture contains 20 mol% cyclohexane and 80 mol% toluene. During the first fraction collected in a fractional distillation, the distillate composition will be enriched in the more volatile component (cyclohexane). Which of the following approximate compositions is the most reasonable for the first distillate?

    About 1:1 cyclohexane : toluene (≈50% cyclohexane)

  • 49

    Which of the following laboratory procedure statements is correct?

    Volatile liquids should be weighed by first recording the mass of the empty vial with its cap.

  • 50

    What term describes the nominal volume of water (or mercury) contained in or delivered by a piece of volumetric glassware at its reference temperature?

    Capacity

  • 51

    A lab analyst dissolved 4.021 g of NaOH in water to prepare 1.00 L of solution. Then 10.00 mL of this solution was titrated with 0.0500 M HCl, requiring 20.32 mL of acid at the endpoint. Based on this result, the lab supervisor could deduce that:

    The burette was rinsed with water instead of HCl

  • 52

    In the maintenance and storage of pH electrodes, which of the following should NOT be done?

    Store the electrode in distilled water to keep the electrode bulb moist during storage

  • 53

    Which of the following is NOT a good sampling practice?

    Collect the sample in a container made of material that will chemically react with the sample

  • 54

    Which crucible should NOT be used for dry ashing because common dry-ashing temperatures exceed its melting point?

    Glass

  • 55

    Multiple extraction is more effective when the extraction is repeated with:

    Small amounts of solvent repeatedly

  • 56

    Which of the following is commonly used for vacuum filtration with filter paper?

    Buchner crucible

  • 57

    Which of the following is most suitable for filtering hot mother liquor during recrystallization?

    Short-stem funnel

  • 58

    What is the process in which a sample is heated to the boiling point of the solvent so that volatile analytes concentrate in the vapor phase and are then condensed and collected?

    Distillation

  • 59

    Which of the following mixtures cannot be effectively separated by simple distillation?

    Milk and water

  • 60

    Which is the correct method to determine the boiling point of an unknown liquid?

    Boil the liquid and place the thermometer bulb in the refluxing vapor (so it reads the vapor temperature)

  • 61

    Which of the following is NOT a reason to use a steam bath for heating in a laboratory?

    Overheating is still possible

  • 62

    What is the main advantage of steam distillation?

    It reduces decomposition of temperature-sensitive (heat-labile) compounds

  • 63

    Fractional distillation is primarily used to separate which type of mixture?

    Two miscible liquids

  • 64

    In a fractionating column, what is the primary function of the packing beads (or plates)?

    Provide surface area for vapors to condense

  • 65

    Which of the following is a common measure of the efficiency of a fractionating column?

    The number of theoretical plates in the column

  • 66

    A student measures the length of a metal rod as 24.5 cm, while the true length is 25.0 cm. What is the percentage relative error in the measurement?

    2.0%

  • 67

    Which statistical test is commonly used to determine whether a particular data point in a dataset can be rejected as an outlier?

    Q-test (Dixon's Q test)

  • 68

    The performance of analytical methods or instruments aims to achieve which of the following?

    High signal-to-noise ratio

  • 69

    Which term refers to all the other components in the mixture besides the substance under investigation?

    Matrix

  • 70

    When qualifying a working standard, which type of reagent is most suitable to use?

    Primary standard

  • 71

    Which of the following are essential requirements for a primary standard?

    All of the above

  • 72

    Which quantitative chemical analysis involves weighing a sample, usually a separated and dried precipitate, to determine the amount of a specific analyte?

    Gravimetric analysis

  • 73

    Which method is widely used for determining the protein content in meat and animal food?

    Kjeldahl method

  • 74

    Conductivity is the ability of a substance to:

    Conduct electric current, which is the reciprocal of resistivity

  • 75

    Which of the following statements about electrical conductivity is not true?

    Increasing temperature has no effect on its value

  • 76

    Chromatography is used to:

    All of the above

  • 77

    A mobile phase in chromatography can be classified as (I) Solid, (II) Liquid, (III) Gas. Which classification(s) apply to the mobile phase?

    Liquid and gas only (II and III).

  • 78

    In thin-layer chromatography (TLC), the mobile phase used in a closed development chamber is typically a mixture of:

    Liquids

  • 79

    What is the basic principle of TLC?

    Different compounds are adsorbed on an adsorbent to different degrees.

  • 80

    Which of the following statements about visualization methods during TLC is true?

    All of the above (spots of colorless compounds are invisible to the eyes; spots can be detected under UV light; spots can be detected by exposing the plate to iodine vapors).

  • 81

    Which type of chromatography is commonly used for structural analysis?

    Partition chromatography

  • 82

    Column chromatography is based on the principle of:

    Differential adsorption

  • 83

    Which of the following can be separated using column chromatography?

    Chlorophylls and carotenoids

  • 84

    Affinity chromatography is primarily used for the analysis and isolation of:

    Antibodies bound to a covalently attached antigen on a cellulose column

  • 85

    An ion exchanger containing the functional group SO3H primarily exchanges which type of ions?

    Cations

  • 86

    Gas-solid chromatography is classified as which type of chromatography based on its basic principle?

    Adsorption

  • 87

    Which of the following statements about adsorption on a polar surface is correct?

    The more polar the solute, the more strongly it will be adsorbed on a polar surface.

  • 88

    Which of the following is useful for the separation of low molecular weight gases?

    Gas-solid chromatography

  • 89

    Which sample preparation technique(s) is/are most suitable for analyzing volatile organic compounds (VOCs) using gas chromatography?

    Purge and trap; Solid-phase microextraction (both I and II)

  • 90

    What is the name of the graph showing the detector's response as a function of elution time, including band shapes, positions, and resolution?

    Chromatogram

  • 91

    Which of the following statements about spectroscopic methods is correct?

    Spectroscopic methods require less time and less amount of sample than classical methods.

  • 92

    Which law describes the linear relationship between absorbance and concentration of an absorbing species in a solution?

    Beer-Lambert's Law

  • 93

    Why is it generally preferable to use absorbance (A) as a measure of absorption rather than percent transmittance (%T)?

    Because A is proportional to the concentration of the analyte, whereas %T is not.

  • 94

    Which of the following procedures is performed to verify that an atomic absorption spectrometer is functioning properly?

    Calibration check

  • 95

    Which of the following is NOT a limitation of Beer-Lambert's law?

    Beer-Lambert's law forms the quantitative basis for all types of absorption spectroscopy of an analyte.

  • 96

    A graphical representation of measuring signal as a function of quantity of analyte is called:

    Calibration curve

  • 97

    The different types of energy associated with a molecule include:

    All of the above

  • 98

    Alcohol and ether are commonly used as solvents. What is a disadvantage of using these solvents to dissolve analytes for spectroscopic analysis in the UV-Visible region?

    They also absorb light in the UV-Visible region, interfering with the measurement

  • 99

    Which of the following is an application of electronic spectroscopy?

    All of the above

  • 100

    The reaction rate is defined as:

    The rate at which the concentration of reactants decreases or the concentration of products increases with time

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    問題一覧

  • 1

    What is 2.34 × 10^5 written in standard decimal form?

    234000

  • 2

    How many significant figures are there in the measurement 3.400 g?

    4

  • 3

    Express the number 0.051065 to four significant figures.

    0.05107

  • 4

    A prediction or possible explanation for a question or problem that can be tested in an experiment is called:

    Hypothesis

  • 5

    Which of the following is best described as having components that can be physically separated?

    Mixture

  • 6

    Which of the following is an extensive property of matter?

    Neither — both density and viscosity are intensive properties

  • 7

    Mass is best defined as:

    The amount of matter in an object

  • 8

    Which of the following will cause the mass of a metal block to increase?

    None of the above

  • 9

    Liquid A has a lower boiling point than liquid B. Which best describes the boiling point of a solution made by mixing A and B?

    Between the boiling points of A and B

  • 10

    Which of the following does NOT indicate that a chemical change has occurred?

    Change in shape

  • 11

    What happens when two materials with different densities, such as oil and water, come into contact?

    Separate based on their densities

  • 12

    Most substances are denser in their solid state than in their liquid state. However, water is unique because:

    Its solid form is less dense than its liquid form.

  • 13

    Determine the actual volume contained in a 50.0 mL volumetric flask given the following data. Mass of water: 50.1227 g. Density of water at 25°C: 0.99707 g/mL.

    50.27 mL

  • 14

    According to the kinetic molecular theory, gas particles are in:

    Continuous random motion

  • 15

    Which of the following assumptions is part of the kinetic molecular theory?

    Gas particles have negligible volume compared to the container.

  • 16

    What is the molar mass of an unknown gas if 1.60 g of the gas occupies a volume of 2.24 L at STP (273.15 K and 1 bar)? (1 atm = 1.01325 bar)

    16.2 g/mol

  • 17

    Which of the following gases behaves most like an ideal gas under standard conditions?

    Helium (He)

  • 18

    Three flasks (labeled 1, 2, 3) each contain the same number of gas molecules at the same temperature. In which flask is the pressure highest?

    The flask with the smallest volume

  • 19

    When water is heated in a beaker, bubbles of air form on the side of the glass before the water begins to boil. This observation indicates that the solubility of gases in water:

    Decreases as temperature increases

  • 20

    Which of the following is true for the C-12 isotope?

    It has 6 protons and 6 neutrons.

  • 21

    Noble gases are chemically inert because they have complete outer electron shells. Which of the following elements is not a noble gas?

    Chlorine

  • 22

    Sodium carbonate is commonly known as:

    Soda ash

  • 23

    Which name does not correctly refer to Hg2Cl2?

    Mercury(II) chloride

  • 24

    Which of the following statements does not describe a nonpolar covalent bond?

    It is a bond between different nonmetal atoms.

  • 25

    When 7 g of carbon reacts completely with 4 g of oxygen, what is the total mass of the product formed?

    11 g

  • 26

    A 1.00 g sample of which compound will produce the highest amount of carbon dioxide after complete combustion with excess oxygen?

    C4H10

  • 27

    The water content of an 875.4 mg sample of cheese was determined using a moisture analyzer. If the final dry mass after analysis is 545.8 mg, what is the % H2O in the cheese?

    37.65%

  • 28

    The substance that does the dissolving and makes up more than 50% of the solution is the:

    Solvent

  • 29

    Which of the following best describes the relationship between viscosity and solubility of a liquid in a solvent?

    Lower viscosity usually results in better solubility due to easier molecular movement

  • 30

    What is the normality of a 5.0 M sulfuric acid solution?

    10.0 N

  • 31

    Which of the following is equivalent to 0.01% by weight?

    100 ppm

  • 32

    A solution has a Cu2+ concentration of 3.0 × 10^-4 M. What is the Cu2+ concentration in parts per million (ppm)? (Molar mass of Cu = 63.55 g/mol)

    19.1 ppm

  • 33

    How many grams of NaOH (40.0 g/mol) are required to prepare 500 mL of 0.500 N NaOH solution? (Assume NaOH is monoprotic so N = M.)

    10.0 g

  • 34

    What is the molarity of a solution prepared by dissolving 72.9 g of HCl (36.46 g/mol) in enough water to make 500 mL of solution?

    4.00 mol/L

  • 35

    A solution of HCl has a molarity of 6.0 M and a density of 1.10 g/mL. Calculate the molality (mol/kg) of the solution. (Molar mass of HCl = 36.46 g/mol)

    6.81 m

  • 36

    What volume of 4.0 M HCl is needed to prepare 1.0 L of a 0.5 M solution?

    0.125 L

  • 37

    A student has three stock solutions: Zn at 2000 ppm, Cd at 1500 ppm, and Pb at 1000 ppm. The student takes 10 mL from each solution and dilutes to 200 mL total. What is the final concentration of each element in the mixture?

    100 ppm Zn, 75 ppm Cd, 50 ppm Pb

  • 38

    Under the Lewis concept of acids and bases, a Lewis acid is a(n):

    Electron pair acceptor

  • 39

    Which of the following substances is basic?

    Milk of magnesia

  • 40

    What is the pH of a 0.10 M NaOH solution?

    13

  • 41

    If the pOH of a solution is 3.5, what is the pH of the solution?

    10.5

  • 42

    Which laboratory test can help distinguish an unknown white solid being NaOH or NH4NO3?

    Aqueous NaOH turns litmus paper blue, while NH4NO3 does not change litmus color.

  • 43

    When chromium changes from an oxidation state of +3 to +6, chromium must:

    Lose 3 electrons

  • 44

    Consider the reaction Mg + 2 H2O → Mg(OH)2 + H2. Which of the following statements is false?

    Mg is the oxidizing agent

  • 45

    In an electrolytic cell, oxidation occurs:

    At the anode

  • 46

    During the electroplating of silver, what happens to the silver ions in solution?

    They are reduced at the cathode to form metallic silver.

  • 47

    An unknown metal nitrate is electrolyzed in water. During the process, X grams of the metal were deposited at the cathode, and simultaneously X grams of copper dissolved into the anolyte solution. Which metal is the most likely identity of the unknown metal?

    Copper (Cu)

  • 48

    A binary liquid mixture contains 20 mol% cyclohexane and 80 mol% toluene. During the first fraction collected in a fractional distillation, the distillate composition will be enriched in the more volatile component (cyclohexane). Which of the following approximate compositions is the most reasonable for the first distillate?

    About 1:1 cyclohexane : toluene (≈50% cyclohexane)

  • 49

    Which of the following laboratory procedure statements is correct?

    Volatile liquids should be weighed by first recording the mass of the empty vial with its cap.

  • 50

    What term describes the nominal volume of water (or mercury) contained in or delivered by a piece of volumetric glassware at its reference temperature?

    Capacity

  • 51

    A lab analyst dissolved 4.021 g of NaOH in water to prepare 1.00 L of solution. Then 10.00 mL of this solution was titrated with 0.0500 M HCl, requiring 20.32 mL of acid at the endpoint. Based on this result, the lab supervisor could deduce that:

    The burette was rinsed with water instead of HCl

  • 52

    In the maintenance and storage of pH electrodes, which of the following should NOT be done?

    Store the electrode in distilled water to keep the electrode bulb moist during storage

  • 53

    Which of the following is NOT a good sampling practice?

    Collect the sample in a container made of material that will chemically react with the sample

  • 54

    Which crucible should NOT be used for dry ashing because common dry-ashing temperatures exceed its melting point?

    Glass

  • 55

    Multiple extraction is more effective when the extraction is repeated with:

    Small amounts of solvent repeatedly

  • 56

    Which of the following is commonly used for vacuum filtration with filter paper?

    Buchner crucible

  • 57

    Which of the following is most suitable for filtering hot mother liquor during recrystallization?

    Short-stem funnel

  • 58

    What is the process in which a sample is heated to the boiling point of the solvent so that volatile analytes concentrate in the vapor phase and are then condensed and collected?

    Distillation

  • 59

    Which of the following mixtures cannot be effectively separated by simple distillation?

    Milk and water

  • 60

    Which is the correct method to determine the boiling point of an unknown liquid?

    Boil the liquid and place the thermometer bulb in the refluxing vapor (so it reads the vapor temperature)

  • 61

    Which of the following is NOT a reason to use a steam bath for heating in a laboratory?

    Overheating is still possible

  • 62

    What is the main advantage of steam distillation?

    It reduces decomposition of temperature-sensitive (heat-labile) compounds

  • 63

    Fractional distillation is primarily used to separate which type of mixture?

    Two miscible liquids

  • 64

    In a fractionating column, what is the primary function of the packing beads (or plates)?

    Provide surface area for vapors to condense

  • 65

    Which of the following is a common measure of the efficiency of a fractionating column?

    The number of theoretical plates in the column

  • 66

    A student measures the length of a metal rod as 24.5 cm, while the true length is 25.0 cm. What is the percentage relative error in the measurement?

    2.0%

  • 67

    Which statistical test is commonly used to determine whether a particular data point in a dataset can be rejected as an outlier?

    Q-test (Dixon's Q test)

  • 68

    The performance of analytical methods or instruments aims to achieve which of the following?

    High signal-to-noise ratio

  • 69

    Which term refers to all the other components in the mixture besides the substance under investigation?

    Matrix

  • 70

    When qualifying a working standard, which type of reagent is most suitable to use?

    Primary standard

  • 71

    Which of the following are essential requirements for a primary standard?

    All of the above

  • 72

    Which quantitative chemical analysis involves weighing a sample, usually a separated and dried precipitate, to determine the amount of a specific analyte?

    Gravimetric analysis

  • 73

    Which method is widely used for determining the protein content in meat and animal food?

    Kjeldahl method

  • 74

    Conductivity is the ability of a substance to:

    Conduct electric current, which is the reciprocal of resistivity

  • 75

    Which of the following statements about electrical conductivity is not true?

    Increasing temperature has no effect on its value

  • 76

    Chromatography is used to:

    All of the above

  • 77

    A mobile phase in chromatography can be classified as (I) Solid, (II) Liquid, (III) Gas. Which classification(s) apply to the mobile phase?

    Liquid and gas only (II and III).

  • 78

    In thin-layer chromatography (TLC), the mobile phase used in a closed development chamber is typically a mixture of:

    Liquids

  • 79

    What is the basic principle of TLC?

    Different compounds are adsorbed on an adsorbent to different degrees.

  • 80

    Which of the following statements about visualization methods during TLC is true?

    All of the above (spots of colorless compounds are invisible to the eyes; spots can be detected under UV light; spots can be detected by exposing the plate to iodine vapors).

  • 81

    Which type of chromatography is commonly used for structural analysis?

    Partition chromatography

  • 82

    Column chromatography is based on the principle of:

    Differential adsorption

  • 83

    Which of the following can be separated using column chromatography?

    Chlorophylls and carotenoids

  • 84

    Affinity chromatography is primarily used for the analysis and isolation of:

    Antibodies bound to a covalently attached antigen on a cellulose column

  • 85

    An ion exchanger containing the functional group SO3H primarily exchanges which type of ions?

    Cations

  • 86

    Gas-solid chromatography is classified as which type of chromatography based on its basic principle?

    Adsorption

  • 87

    Which of the following statements about adsorption on a polar surface is correct?

    The more polar the solute, the more strongly it will be adsorbed on a polar surface.

  • 88

    Which of the following is useful for the separation of low molecular weight gases?

    Gas-solid chromatography

  • 89

    Which sample preparation technique(s) is/are most suitable for analyzing volatile organic compounds (VOCs) using gas chromatography?

    Purge and trap; Solid-phase microextraction (both I and II)

  • 90

    What is the name of the graph showing the detector's response as a function of elution time, including band shapes, positions, and resolution?

    Chromatogram

  • 91

    Which of the following statements about spectroscopic methods is correct?

    Spectroscopic methods require less time and less amount of sample than classical methods.

  • 92

    Which law describes the linear relationship between absorbance and concentration of an absorbing species in a solution?

    Beer-Lambert's Law

  • 93

    Why is it generally preferable to use absorbance (A) as a measure of absorption rather than percent transmittance (%T)?

    Because A is proportional to the concentration of the analyte, whereas %T is not.

  • 94

    Which of the following procedures is performed to verify that an atomic absorption spectrometer is functioning properly?

    Calibration check

  • 95

    Which of the following is NOT a limitation of Beer-Lambert's law?

    Beer-Lambert's law forms the quantitative basis for all types of absorption spectroscopy of an analyte.

  • 96

    A graphical representation of measuring signal as a function of quantity of analyte is called:

    Calibration curve

  • 97

    The different types of energy associated with a molecule include:

    All of the above

  • 98

    Alcohol and ether are commonly used as solvents. What is a disadvantage of using these solvents to dissolve analytes for spectroscopic analysis in the UV-Visible region?

    They also absorb light in the UV-Visible region, interfering with the measurement

  • 99

    Which of the following is an application of electronic spectroscopy?

    All of the above

  • 100

    The reaction rate is defined as:

    The rate at which the concentration of reactants decreases or the concentration of products increases with time