Exam 1 Flashcards
It is ______ effective to do three extractions with 100 mL each time than to to do one extraction with 300 mL.
More
when the pH is changed of a solute that is an acid/base the ______ also changes.
charge
(neutral/charged) species is more soluble in an organic solvent
neutral
(neutral/charged) species is more soluble in an aqueous solution.
charged
What must one do in order to extract a base into water?
a low enough pH must be used in order to convert B to BH+
What must one do in order to extract an acid HA into water?
a high enough pH must be used to convert HA to A-
The _____ the pH, the more HA in aqueous solution
Higher
The _____ the pH, the more B in aqueous solution
lower
most complexes that can be extracted into organic solvents are (charged/neutral).
neutral
what is the most common organic ligand used to separate metal ions from one another (which is also a weak acid)?
8-hydroxyquinoline
What does the distribution coefficient for a metal ion extraction depend on?
pH and ligand concentration
Who is considered the father of chromatography?
Russian botanist: Mikhail Tswett
what is chromatography
method.
consists of a mobile phase and stationary phase.
the mobile phase (solvent) moves through the stationary phases separating the mixture into components
What is usually the mobile phase?
a liquid or a gas moving through the column
What is usually the stationary phase?
a viscous liquid or solid particles.
Fluid entering the column is called ________
eluent
Fluid emerging from the end of the column is called _________
eluate
Define elution.
the process of passing liquid or gas through a chromatography column.
Name the two types of columns.
packed column
open tubular column
what is a packed column?
column filled with particles of stationary phase
what is a open tubular column?
a narrow, hollow capillary with sationary phase coated on the inside walls
Name the 5 types of chromatography
- Adsorption chromatography
- Partition chromatography
- Ion-exchange chromatography
- Size exclusion chromatography
- Affinity chromatography
Briefly describe:
Adsorption chromatography
Partition chromatography
Ion-exchange chromatography
Size exclusion chromatography
Affinity chromatography
Solute is adsorbed on the surface of a solid stationary phase.
In adsorption chromatography, the more strongly a solute is adsorbed, the ______ it travels through the column.
slower
Briefly describe:
Absorption chromatography
Partition chromatography
Ion-exchange chromatography
Size exclusion chromatography
Affinity chromatography
Solute is dissolved in liquid stationary phase which is bonded to the surface of a column