Deck 1: The Analytical Process

Question 1

____________________ is the substance being measured during a chemical analysis.

A)Bulk
B)Lot
C)Sample
D)Analyte
E)Aliquot

Answer 1

Analyte

Question 2

A(n)________________________________________is a plot of detector response as a function of analyte concentration.The curve is constructed using________________________________________containing known concentrations of the analyte of interest.

A)analyte curve;response solutions
B)response curve;standard solutions
C)analyte curve;analyte solutions
D)calibration curve;standard solutions
E)response curve;response solutions

Answer 2

calibration curve;standard solutions

Question 3

____________________ is the series of procedures applied to a sample prior to analysis.

A)Pre-analysis clean up
B)Sample preparation
C)Filler elimination
D)Matrix removal
E)Lot cleaning

Answer 3

Sample preparation

Question 4

Solid-phase extraction is a sample preparation technique.Which of the following statements is(are)NOT true for an aqueous solid-phase extraction?
I Solid-phase extraction separates analyte from the sample matrix using a chromatography stationary phase.
II An aliquot of the aqueous sample is applied to the solid-phase extraction tube,washing the sample with additional sample and then a water wash.
III The analyte sticks to the column and the water wash removes all species that do not adhere to the column.
IV An organic solvent is used to wash the analyte from the column.
V The organic phase containing the analyte is evaporated to dryness and the solid is dissolved in water,ready for analysis.

A)III
B)I
C)II and III
D)IV
E)II

Question 5

____________________ chemical analysis is the measurement of how much of a chemical substance is present.____________________ chemical analysis is the determination of what is present in a sample.

A)Quantitative;Qualitative
B)Stoichiometric ;Qualitative
C)Qualitative;Quantitative
D)Stoichiometric ;Identification
E)Quantitative;Identification

Question 6

Which statement is NOT true?

A)For a random heterogeneous material differences in composition are random and on a fine scale.
B)A representative random sample is collected from randomly selected portions of the sample for a given number of times.
C)A segregated heterogeneous material has large regions with obviously different compositions.
D)A representative composite sample is collected from a segregated material by taking portions from each region,the number of collected portions proportional to the area of the region.
E)All are true statements.

Question 7

____________________ is any chemical of interest.

A)Analyte
B)Species
C)Replicate
D)Aliquot
E)Bulk

Question 8

Which is NOT a general step in the analytical process?

A)Sample Preparation
B)Selecting analytical procedures
C)Make policy
D)Reporting and interpretation
E)Analysis

Question 9

A sample with a uniform chemical composition is a________________________________________sample.

A)homologous
B)homogeneous
C)uniform
D)consistent
E)heterogeneous

Question 10

________________________________________are repeated measurements to assess the variability in the analysis and to guard against a gross error in the analysis of a single aliquot.

A)Replicate measurements
B)Aliquots
C)Sampling
D)Analysis
E)Error measurements

Question 11

A(n)____________________ is a suspension of a solid in a liquid.

A)slurry
B)colloid
C)gel
D)supernatant
E)allotrope

Question 12

____________________ is the transformation of an interfering species into a form that is not detected.

A)Interference
B)Masking
C)Obscurance
D)Cloaking
E)Camouflaging

Question 13

A(n)________________________________________is used to grind solids into smaller particles.

A)orbital shaker
B)vortexer
C)mixer
D)mortar and pestle
E)centrifuge

Question 14

The liquid above the packed solid following a centrifugation is the____________________ .

A)solvonatant
B)analyte
C)serum
D)decanted
E)supernatant

Question 15

For separations,the plot of detector response versus time is a(n)____________________ and the area under the peak is____________________ to the quantity of compound passing through the detector.

A)column plot;proportional
B)column plot;inversely proportional
C)chromatogram;proportional
D)chromatogram;inversely proportional
E)absorbance spectrum;proportional

Question 16

When extracting a sample with a liquid,the liquid is____________________ from the sample.

A)transferred
B)drained
C)decanted
D)effused
E)dispensed

Question 17

____________________ occurs when a species other than analyte increases or decreases the analytical signal and makes it appear that the concentration is greater or less than the real concentration.

A)Interference
B)Masking
C)Aliquots
D)Disruption
E)Intervention

Question 18

____________________ is the process of procuring a representative sample to analyze.

A)Inspection
B)Examination
C)Representation
D)Sampling
E)Partaking

Question 19

A(n)____________________ sample is a sample where the chemical composition differs from place to place.

A)variable
B)homogeneous
C)random
D)inconsistent
E)heterogeneous

Question 20

A calibration curve for the determination of aspirin is constructed from known concentration aspirin solutions,mg/mL,and the HPLC peak area's for each standard.If the equation is y = 12.565x − 0.71,what is the concentration for an unknown that has a peak area of 83.5?