Chapter 5

Question 1

In solution, the effect of ions present but not part of the reaction of interest

Answer 1

Common ion effect

Question 2

A sample preparation technique that attacks and destroys most of the matrix, leaving analytes behind; primarily for inorganics and metals

Answer 2

Digestion

Question 3

Electrostatic attractions or repulsions between partially (+) or (-) regions of two polar molecules

Answer 3

Dipole-dipole interactions

Question 4

In drug analysis, a simple one-step extraction method in which a solvent is added to a solid sample. Typically, the next step is GCMS analysis of the extract

Answer 4

Dry extraction

Question 5

The material that exists in a SPE or chromatographic column

Answer 5

Eluant

Question 6

The solvent or mobile phase used in SPE or chromatography

Answer 6

Eluent

Question 7

The ratio of products to reactants raised to the power of the coefficients

Answer 7

Equilibrium constant

Question 8

The gas above a solvent or sample into which analytes can volatize

Answer 8

Headspace

Question 9

An equation used to describe buffers and other weak acids; relates pH to pKa and concentrations of acid and conjugate base

Answer 9

Henderson-Hasselbalch equation

Question 10

The law that relates partial pressure of a substance above a solution to the concentration in the solution; KH * Pa = [A]

Answer 10

Henry’s law

Question 11

“Water loving”; water soluble; usually lipophobic

Answer 11

Hydrophilic

Question 12

“Water hating”; water insoluble; usually lipophilic

Answer 12

Hydrophobic

Question 13

The water solubility of a drug alone, not in the ionized form

Answer 13

Intrinsic solubility (So)

Question 14

Electrostatic attractions or repulsions between an ion and a partially (+) or (-) region of a polar molecule

Answer 14

Ion-dipole interactions

Question 15

Electrostatic attractions and interactions between two ions

Answer 15

Ion-ion interactions

Question 16

In a large molecule, a site where ionization can occur typically in an acid/base manner

Answer 16

Ionization center

Question 17

The pH at which a molecule with multiple ionization centers is neutral

Answer 17

Isoelectric point (isoelectric pH)

Question 18

Generic symbol for the equilibrium constant

Answer 18

K

Question 19

When a chemical equilibrium exists, any disturbance of the system will result in the system compensating

Answer 19

Le Châtelier’s principle

Question 20

A rule of thumb concerning polarity and solubility. A polar molecule will dissolve in a polar solvent but not in a non-polar one

Answer 20

Like dissolves like (LdL)

Question 21

Literally, “fat loving”; molecules that are more soluble in fats and oils than in water

Answer 21

Lipophilic

Question 22

“Fat hating”; insoluble in nonpolar solvents; are usually hydrophilic

Answer 22

Lipophobic

Question 23

In solid phase extraction or chromatography, the phase that moves over the solid or stationary phase; may be polar, nonpolar, or inert

Answer 23

Mobile phase

Question 24

Separation or chromatography using a polar stationary phase and a nonpolar mobile phase

Answer 24

Normal phase

Question 25

The pH at which a drug with an ionizing center is most soluble

Answer 25

pHmax

Question 26

The -log of the quantity of interest such as pH or pKa

Answer 26

pK value

Question 27

Arises from the asymmetric electron distribution around a molecule; leads to partially positive and partially negative areas

Answer 27

Polarity

Question 28

The comparative affinity of a compound to different phases such as two different solvents; the basis of partitioning, separations, and chromatography

Answer 28

Relative affinity

Question 29

In TLC, the distance that a compound migrates relative to the starting point

Answer 29

Retention factor

Question 30

Separation or chromatography using a nonpolar stationary phase and a polar mobile phase

Answer 30

Reversed phase

Question 31

An extraction in which one of the phases involved in the selective partitioning is bound to a solid support

Answer 31

Solid phase extraction

Question 32

Extraction into a solid phase coated on a microfiber. The pre-concentrated analytes are typically introduced directly in the injector of a GC

Answer 32

Solid phase microextraction

Question 33

S, calculated using Ksp

Answer 33

Solubility

Question 34

Use of a solvent to extract an analyte or analytes from a matrix

Answer 34

Solvent extraction

Question 35

A measure of the ability of a solvent to elute a material in solid phase extractions or chromatography, based on relative polarity

Answer 35

Solvent strength

Question 36

A solid immobile material to which an active material is bound; the stationary phase in solid phase extraction or chromatography; may be polar or nonpolar

Answer 36

Stationary phase

Question 37

Chromatography in which the solid phase is coated on a support such as glass and solvent is drawn up by capillary action

Answer 37

Thin-layer chromatography (planar chromatography)