Lec 4 Flashcards
The solvent poured through. It is in liquid or gas form. Also called eluent
Mobile phase
Solid base of powder packed into the column, where the mobile phase flows. Should be in solid or liquid form.
Stationary phase
The solid material which serves as the stationary phase in the adsorption chromatography.
Adsorbent
A solid material that supports the liquid film in partition chromatography.
Support
The process where mobile phase is allowed to flow over the adsorbent or support
Development
The analyte material that emerges from the chromatograph.
Eluate
Component molecules of the substance being separated. Also substances being dissolved.
Solutes
The process where the separated substances on the chromatogram are washed off the adsorbent.
Elution
It is to become separated into constituent parts. A technique developed to separate plant pigments into colored bands.
Resolution
The process of separation of a chemical mixture into different components based on their physical-chemical characteristics and interaction of molecules with the mobile and stationary phase through a support medium.
Chromatography
4 Physico-chemical properties used as a basis in the separation of soluble components in a solution
Differences in:
1. Adsorption to the medium
2. Relative solubilities of mobile & stationary phase
3. Ionic attraction to the sorbent
4. Penetration into a sorbent gel
Type of chromatography that includes:
Classical Adsorption chromatography & Ion exchange
Liquid-Solid
Type of chromatography that includes:
Classical Partition Paper Chromatography & Thin Layer Chromatography
Liquid-Liquid
Type of chromatography that includes:
Gas Liquid Chromatography
Gas-Liquid
In Adsorption:
• Mobile phase should be in ____ form.
• Stationary phase should be in ___ form.
• Mobile phase is in liquid or gas form
• Stationary phase is in solid or liquid form
In Partition:
• Mobile phase should be in ___ form
• Stationary phase should be in ___ form
• Mobile phase is in liquid or gas form
• Stationary phase is in liquid form
_____ Chromatography:
The affinity of the components of a mixture for the adsorbent and the solubility in the mobile phase result in the resolution of the mixture.
Adsorption Chromatography (principle)
The Physical forces that control Adsorption chromatography
Hydrogen bonding,
Electrostatic,
Dispersive interactions,
Van der Waal Forces
Properties of a Good adsorbent
• insoluble to the solvent used
• neither react with separated substance, nor catalyze their decomposition
• colorless adsorbent, if colored separated substance
____ Chromatography:
Separation of solutes is based on relative solubility of the organic nonpolar solvent and the aqueous polar solvent
Partition chromatography (principle)
• Organic molecules with unequal sharing of electrons
• hydrophilic
• partially soluble in water
Polar groups
• Organic molecules predominantly made of covalent bonds with equal sharing of electrons
• hydrophobic
Nonpolar groups
K = solute in stationary phase ÷ solute in mobile phase
Partition of Coefficient (formula)