Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CH304 > Final exam vocab > Flashcards

Final exam vocab Flashcards

1
Q

length of a chromatography column divided by plate number of the column. Calculated as the variance of the analyte band divided by the distance, x, it has traveled

A

plate height

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

a chromatographic separation utilizing a polar stationary phase and a less polar mobile phase

A

normal phase hplc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

in gas chromatography, a length of empty, silanized capillary ahead of the chromatography column placed there to improve the peak shape of solutes that elute close to solvent when large volumes of solvent are injected or when the solvent has a very different polarity from that of the stationary phase.

A

retention gap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

In chromatography, the distance per unit time traveled by the mobile phase.

A

linear flow rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

A technique in which separation is based on differences in the solubility of sample components in the stationary phase in gas chromatography and in the mobile and stationary phases in liquid chromatography.

A

partition chromatography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A technique in which solute ions are retained by oppositely charged sites in the stationary phase.

A

ion exchange

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

A technique in which the stationary phase has a porous structure into which small molecules can enter but large molecules cannot. Molecules are separated by size, with larger molecules moving faster than smaller ones

A

size exclusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

In chromatography, a hollow capillary column whose walls have high-surface-area porous solid particles adhering to the column wall.

A

porous-layer open tubular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Liquid chromatography using a single solvent (or single solvent mixture) for the
mobile phase continuously throughout the separation.

A

isocratic elution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Splitless gas chromatography injection technique in which solutes are condensed at the start of the column by setting the initial column temperature at least 100°C below the boiling points of the solutes of interest. Solvent and
low-boiling components are eluted rapidly, but high-boiling solutes remain in a narrow band at the beginning of the column.

A

solvent trapping

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Chromatographic peak where there is a gradual rise and abrupt fall of the peak.
B/A < 1

A

fronting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The log of the ratio of the irradiance striking the sample and the radiant power emerging from the other side.

A

absorbance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The fraction of incident radiation that passes through a sample.

A

transmittance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Process in which a molecule emits a photon due to transition between states of the same spin multiplicity (e.g., singlet  singlet ).

A

fluorescence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Emission of light during a transition between states of different spin multiplicity
(e.g., Triplet  Singlet ).

A

phosphorescence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A graph of luminescence intensity versus luminescence wavelength (or frequency or wavenumber), obtained with a fixed excitation wavelength.

A

emission spectrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

A graph of luminescence (measured at a fixed wavelength) versus excitation frequency or wavelength.

A

excitation spectrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Any state of an atom or a molecule having more than the minimum possible energy.

A

excited state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

State of an atom or a molecule with the minimum possible energy.

A

ground state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Electronic state in which all electron spins are paired.

A

singlet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

An electronic state in which there are two unpaired electrons.

A

triplet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Process in which emission from an excited molecule is decreased by energy transfer to another molecule

A

quenching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

In luminescence, a decrease in emission intensity due to absorption of excitation or emission irradiance by analyte molecules

A

self-absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

the range of wavelengths or frequencies of an absorption or emission band, typically measured at a height equal to half of the peak height

A

bandwidth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The application of numerical algorithms to data to reduce noise

A

digital smoothing

26
Q

In atomic absorption, periodic blocking of the beam allows a distinction to be made between light from the source and light from the flame.

A

beam chopping

27
Q

Improvement of a signal by averaging successive scans.

A

signal averaging

28
Q

Relative population of two states at thermal equilibrium – related to the degeneracy of the ground and excited states, the energy gap between them, the temperature, and a constant.

A

boltzman distribution

29
Q

A molecule moving toward a source of radiation experiences a higher frequency than one moving away from the source.

A

doppler effect

30
Q

In spectroscopy, line broadening due to collisions between molecules

A

pressure broadening

31
Q

Most intense peak in a mass spectrum

A

base peak

32
Q

Integer mass of the species with the most abundant isotope of each of the constituent atoms.

A

nominal mass

33
Q

In mass spectrometry, an ion that has not lost or gained any atoms during ionization.

A

molecular ion

34
Q

Process of breaking a liquid into a mist of fine droplets.

A

nebulization

35
Q

A suspension of very small liquid or solid particles in air or gas.

A

aerosol

36
Q

A sample not intended to contain analyte

A

blank

37
Q

Range of analyte concentration over which a change in

concentration gives a change in detector response

A

dynamic range

38
Q

Concentration range over which the change in detector
response is proportional to the change in analyte
concentration

A

linear range

39
Q

A liquid remaining above a solid after precipitation

A

supernatant

40
Q

A suspension of a solid in a solvent

A

slurry

41
Q

All substances found within a material

A

matrix

42
Q

Moles of solute per liter of solution

A

molarity

43
Q

Moles of solute per kilogram of solution

A

molality

44
Q

Mass of a substance per unit volume

A

density

45
Q

Mass of solute per mass of total solution (multiplied by

100)

A

weight percent

46
Q

Volume of solute per volume of total solution

multiplied by 100

A

volume percent

47
Q

Micrograms of analyte per gram (or milliliter) of sample

A

ppm

48
Q

Nanograms of analyte per gram (or milliliter) of sample

A

pbb

49
Q

The bell-shaped curve obtained by plotting frequency

versus deviation from the mean

A

guasssian curve

50
Q

All of the digits of a number that are known with

certainty plus the first uncertain digit

A

significant figures

51
Q

Describes the spread in results when one person uses
one procedure to analyze the same sample by the same
method with the same equipment multiple times

A

repeatability

52
Q

Describes the variation observed when an assay is
performed by different people on different instruments
on different days in the same lab

A

intermediate precision

53
Q

Describes the spread in results when different people in
different labs using different equipment each follow the
same procedure with the same kind of sample

A

reproducibility

54
Q

It is an analysis of a solution formulated to contain a
known concentration of analyte. It is the analyst’s own
check that procedures and instruments are functioning
correctly.

A

check standard

55
Q

A datum that is far from other points

A

outlier

56
Q

A graph showing the value of some property versus
concentration of analyte. When the corresponding
property of an unknown is measured, its concentration
can be determined from the graph.

A

calibration curve

57
Q

A measure of how close a measured value is to the

“true” value

A

accuracy

58
Q

A change in analytical sensitivity (slope of calibration) caused by anything in the sample other than analyte.

A

matrix affect

59
Q

Slow change in the response of an instrument due to various causes such as changes in electrical components with temperature, variation in power-line voltage to an instrument, and aging of components within instruments.

A

drift

60
Q

Smallest amount of analyte that can be measured with

reasonable accuracy. Usually taken as 10 times the standard deviation of a blank or low-concentration sample

A

quantitation limit

61
Q

Visual representation of confidence intervals for a Gaussian distribution - warns us when a property being monitored strays dangerously far from an intended target value.

A

control chart

CH304 (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions