Standard Calibration

Question 1

Method of identifying a chemical species

Answer 1

Qualitative Analysis

Question 2

Method to determine the amount of a constituent.

Answer 2

Quantitative Analysis

Question 3

Quantitative methods can be classified as gravimetric, volumetric, or instrumental.

Question 4

Used for samples with masses > 0.1 g.

Answer 4

Macro Analysis

Question 5

Used for samples with masses of 0.01 to 0.1 g.

Answer 5

Semimicro Analysis

Question 6

Used for samples with masses of 10^-4 to 10^-2 g.

Answer 6

Micro Analysis

Question 7

used for samples with masses of < 10^-4

Answer 7

Ultramicro Analysis

Question 8

Present in the range of 1 to 100% by mass.

Answer 8

Major constituents

Question 9

Present in the range of 0.01 to 1% by mass.

Answer 9

Minor constituents

Question 10

Present in the range of 100 ppm (0.01%) and 1 ppb.

Answer 10

Trace constituents

Question 11

Present in amounts lower than 1 ppb.

Answer 11

Ultratrace constituents

Question 12

Occur when extraneous species in the matrix interfere with determination of the analyte.

Answer 12

Matrix effects

Question 13

Samples are analyzed, but constituents or concentrations are determined.

Question 14

Acquiring a representative fraction of the material of interest. It is often the most difficult aspect of an analysis.

Answer 14

Sampling

Question 15

Items chosen for analysis.

Answer 15

Sampling units or sampling increments

Question 16

The collecting of sampling units or increments. A miniature replica of the entire mass of material to be analyzed

Answer 16

Gross sample

Question 17

The gross sample is usually reduced in size and homogenized to create the laboratory sample for analysis.

Question 18

Two goals of the sampling process.

Answer 18

To obtain a mean analyte concentration that is an unbiased estimate of the population mean.

To obtain a variance in the measured analyte concentration that is an unbiased estimate of population variance.

Question 19

A state intermediate between a suspension and a solution.

Answer 19

Colloid

Question 20

Mimics the steps in a determination that would be taken by a human analyst.

Answer 20

Batch or discrete approach

Question 21

Involve inserting the sample into a flowing stream where several operations can be performed before the sample passes through a flow-through detector.

Answer 21

Continuous flow methods

Question 22

Divide a sample into discrete samples separated by gas bubbles that confine the sample and minimize cross-contamination.

Answer 22

Segmented-flow analyzers

Question 23

A band-spreading or mixing phenomenon that results from the coupling of fluid flow with molecular diffusion.

Answer 23

Dispersion

Question 24

Mass transport due to a concentration gradient.

Answer 24

Diffusion

Question 25

Mass transport due to a concentration gradient.

Answer 25

Diffusion

Question 26

A\continuous flow approach in which samples are injected into a flowing stream containing one or more reagents.

Answer 26

Flow injection analysis (FIA)

Question 27

Determines the relationship between the analytical response and the analyte concentration.

Answer 27

Calibration

Question 28

Usually used to determine this relationship.

Answer 28

Chemical Standards

Question 29

Constituents of the sample other than the analyte.

Answer 29

Concomitants

Question 30

Concomitants that interfere with the determination of the analyte.

Answer 30

Interferents or interference

Question 31

Procedures that involve comparing a property of the analyte or the product of a reaction with the analyte with standards to determine if the property matches or nearly matches the standard.

Answer 31

Null comparison or isomation methods

Question 32

Determine whether an analyte concentration exceeds or is less than a threshold level.

Answer 32

Comparator

Question 33

In titration, the analyte reacts with a standardized reagent (the titrant) in a known stoichiometric manner until the titration reaction is complete.

Question 34

In external standard calibration, a series of standard solutions is prepared and used to establish the instrument calibration function from analysis of the instrument response as a function of the known analyte concentrations.

Question 35

A plot of instrument response versus known analyte concentrations is used to produce a calibration curve (also called a working curve).

Question 36

Provides a means to objectively determine the best fit line to data points, such as those in a calibration curve, and for specifying the uncertainties associated with its subsequent use.

Answer 36

Regression analysis

Question 37

The vertical deviation of each point from the straight line.

Answer 37

Residual

Question 38

The standard deviation about regression, standard error of the estimate, and standard error are all terms for the same value, which is a rough measure of the magnitude of a typical deviation from the regression line

Question 39

Used to correct a raw analytical response.

Answer 39

Blank

Question 40

Identical to the solvent but without the analyte but is often too difficult or impossible to prepare.

Answer 40

Ideal Blank

Question 41

Real blanks are either solvent blanks, which contain the same solvent as the sample, or reagent blanks that contain the solvent plus all the reagents used in sample preparation.

Question 42

Involves adding the interfering species to all the samples, standards, and blanks so that the interference effect becomes independent of the original concentration of the interfering species in the sample.

Answer 42

Saturation method

Question 43

A species that is added to samples, standards, and blanks in sufficient amounts to make the analytical response independent of the concentration of the interfering species.

Answer 43

Matrix modifier

Question 44

Reacts selectively with interfering species to form a complex that does not interfere.

Answer 44

Masking agent

Question 45

Attempts to duplicate the sample matrix by adding the major matrix constituents to the standard and blank solutions.

Answer 45

Matrix-matching method

Question 46

A reference species, chemically and physically similar to the analyte that is added to samples, standards, and blanks.

Answer 46

Internal Standard

Question 47

A known amount of a reference species is added to all the samples, standards, and blanks and the measurement response is the ratio of the analyte response to the reference species response.

Answer 47

Single-point addition

Question 48

Additions of known amounts of standard analyte solution are made to several portions of the sample, and a multiple additions calibration curve is obtained.

Answer 48

Multiple addition

Question 49

It is a numerical expression representing the performance or efficiency of a given device, material, method, or procedure.

Answer 49

Figure of merit

Question 50

The change in the measured quantity per unit change in analyte concentration. This is the slope of the calibration curve.

Answer 50

Calibration sensitivity

Question 51

Scatter in the response

Answer 51

Noise

Question 52

The ratio of calibration curve slope to the standard deviation of the analytical signal at a given analyte concentration.

Answer 52

Analytical Sensitivity

Question 53

The smallest concentration that can be reported with a given level of confidence.

Answer 53

Detection limit, DL

Question 54

Refers to the concentration range over which the analyte can be determined using a linear calibration curve.

Answer 54

Linear dynamic range

Question 55

A sequential plot of some quality characteristic that is important in quality assurance.

Answer 55

Control Chart

Question 56

If the mean value remains between the LCL and the UCL, an instrument is in statistical control.

Question 57

Transformations do not give good estimates if the errors are not normally distributed.