CHEM: CHROMA Flashcards
• Is a technique used to separate and identify the
components of a mixture.
CHROMATOGRAPHY
• Works by allowing the molecules present in the
mixture to distribute themselves between a
stationary and a mobile medium.
• Molecules that spend most of their time in the
mobile phase are carried along faster.
CHROMATOGRAPHY
is a laboratory technique that
separates components within a mixture by using
the differential affinities of the components for a
mobile medium and for a stationary adsorbing
medium through which they pass
CHROMATOGRAPHY
showing a difference, distinctive
Differential
natural attraction or force between things
Affinity
gas or liquid that carries the components (mobile phase)
Mobile Medium
the part of the apparatus that does not move with the sample (stationary phase)
Stationary Medium
examine a mixture, its components, and their relations to one another
Analyze
determine the identity of a mixture or components based on known components
Identify
separate components in order to isolate one of interest for further study
purify
determine the amount of the a mixture and/or the components present in the sample
Quantify
can also be used to separate the colored pigments in plants
Chromatography
(t or f)
We can determine the RF (or retardation factor) by
measuring the distance the pigments traveled up
the strip and the distance the water traveled
true
For substances that are very soluble in the liquid Rf
will be close to
1
For substances that are rather insoluble in the liquid
Rf will be close to
0
• Separates dried liquid samples with a liquid solvent
(mobile phase) and a paper strip (stationary phase)
PAPER CHROMATOGRAPHY
the movement of liquid within the spaces of a porous material due to the forces of adhesion, cohesion, and surface tension.
Capillary Action
the degree to which a material (solute)
dissolves into a solvent. Solutes dissolve into
solvents that have similar properties.
Solubility
(t of f)
Separation of components depends on both their
solubility in the mobile phase and their differential
affinity to the mobile phase and the stationary
phase.
true
uses an absorbent material on flat glass or plastic
plates.
THIN LAYER CHROMATOGRAPHY
It is used to detect pesticide or insecticide residues
in food.
THIN LAYER CHROMATOGRAPHY
is also used in forensics to analyze the dye composition of fibers.
THIN LAYER CHROMATOGRAPHY
(t or f)
Most samples are not colored and need to be visualized with a UV lamp.
true
is used in airports to detect bombs and is used in
forensics in many different ways.
GAS CHROMATOGRAPHY
It is used to analyze fibers on a persons body and
also analyze blood found at a crime scene.
GAS CHROMATOGRAPH
is used to move a gaseous mixture through a column of absorbent material
Helium
, called the Mobile Phase,
gas mixture
usually tightly packed into a copper tube called the Column…
- which separates the gas stream into its particular components based on how “quickly” they move through the stationary phase.
Stationary Phase
generates an electrical signal which is sent to a Recorder
Detector
to record the signal.
Recorder
A sample mixture is passed through a column
packed with solid particles which may or may not be
coated with another liquid.
LIQUID CHROMATOGRAPHY
With the proper solvents, packing conditions, some
components in the sample will travel the column
more slowly than others resulting in the desired
separation.
LIQUID CHROMATOGRAPHY
• is used in the world to test water samples to look
for pollution in lakes and rivers.
• is used to analyze metal ions and organic
compounds in solutions.
LIQUID CHROMATOGRAPHY
uses liquids which may incorporate insoluble
molecules.
LIQUID CHROMATOGRAPHY
(adsorption chromatography)
a. Normal Phase LSC
b. Reverse Phase LSC
Liquid/Solid Chromatography
(partition chromatography)
a. Normal Phase LLC
b. Reverse Phase LLC
Liquid/Liquid Chromatography
(exclusion chromatography)
Gel Permeation Chromatography
The stationary solid surface is coated with a 2nd
liquid (the Stationary Phase) which is immiscible in
the solvent (Mobile) phase.
Partitioning of the sample between 2 phases delays
or retains some components more than others to
effect separation.
LIQUID-LIQUID CHROMATOGRAPHY
separation of ____________ is based on the competition of different ionic compounds of the sample for the active sites on the ion-exchange resin (column-packing).
Ion-exchange Chromatography
is a mechanical sorting of molecules based on the size of the molecules in solution.
Gel-Permeation Chromatography
is a form of column chromatography used frequently in biochemistry and analytical chemistry to separate,
identify, and quantify compounds.
HIGH PERFORMANCE LIQUID CHROMATOGRAPHY
utilizes a column that holds chromatographic packing
material (stationary phase), a pump that moves the
mobile phase(s) through the column, and a detector
that shows the retention times of the molecules.
HIGH PERFORMANCE LIQUID CHROMATOGRAPHY
uses a polar stationary phase and a non-polar mobile phase, and works effectively for relatively polar analytes
Normal Phase Chromatograaphy
has a non-polar stationary phase and an aqueous, moderately polar mobile phase
Reversed Phase Chromatography
