prefinal Flashcards
The power of chromatography comes from its ability to _____ and determine their respective identity (chemical structure) and concentration.
separate a mixture of compounds or analyte
The power of chromatography comes from its ability to separate a mixture of compounds or analyte and determine their respective ___ and ___
identity (chemical structure) and concentration.
It is the technique for the separation, purification, and testing of compounds.
Chromatography
The term “chromatography” is derived from Greek words ____ and ____
Chroma (Colour) and Graphein (to write)
It is a separation method where the analyte is combined within a liquid or gaseous mobile phase.
Chromatography
Chromatography is the technique for the ___,___, and ___ of compounds.
separation, purification, and testing
It is the separation of colored compounds on a suitable adsorbent.
Chromatography
It may be defined as a process in which a solution of a mixture containing inert material, drug principles, and impurities is separated into its components while moving through a bed of fixed
Chromatography
Principal Objectives of Chromatography
- Resolution of mixture into a constituent parts
- Determination of homogeneity.
- Comparison of substance suspected of being identical
- Purification
- Concentration of substance from dilute solutions.
- Identification and control of technical products.
- Quantitative separation from the complex mixtures.
- Identification of molecular structure.
Types of Chromatography
Adsorption Chromatography
Thin Layer Chromatography
Column Chromatography
Partition Chromatography
Different compounds are adsorbed on the adsorbent to different degrees based on the absorptivity of the component.
Adsorption Chromatography
A mobile phase is made to move over a stationary phase, thus carrying the components with higher absorptivity to a lower distance than that with lower absorptivity.
Adsorption Chromatography
The mixture of substances is separated into its components with the help of a glass plate coated with a very thin layer of adsorbent, such as silica gel and alumina.
Thin Layer Chromatography
The technique used to separate the components of a mixture using a column of suitable adsorbent packed in a glass tube.
Column Chromatography
It is the material placed in the column to adsorb the drug.
Adsorbent
Examples of Adsorbents
purified siliceous earth
activated alumina
silica gel
calcium carbonate.
A continuous differential partitioning of components of a mixture into a stationary phase and mobile phase takes place.
Partition Chromatography
The example of partition chromatography can be seen in:
Paper Chromatography
In this process, chromatography paper is used as a stationary phase which is suspended in a mixture of solvents that act as a mobile phase.
Partition Chromatography
In Partition Chromatography, chromatography paper is used as a __
Stationary Phase
In Partition Chromatography the mixture of solvents act as a ___
Mobile Phase
It is a solvent used in the separation of substances
Eluant
It is a solution obtained by elution
Eluate
It is the method of separation of any organic component present in an aqueous solution.
Differential Extraction
In this process, we use an organic solvent for which the solubility of the desired compound is more than compared to that in water.
Differential Extraction
In Differential Extraction, ___ is used for which the solubility of the desired compound is more than compared to that in water.
Organic Solvent
In Differential Extraction, the organic solvent is chosen such that it is ____ so that it can form layers and can be separated easily using a separating funnel.
immiscible with the aqueous solution
Chromatography is mainly used for the separation, isolation and purification of proteins from complex sample matrices.
Bio Analytical Chemistry
Proteins occur alongside numerous other compounds such as ___
Lipids and Nucleic Acids
Branch of electrochemistry which deals with the study and measurement of electrode potentials.
Potentiometry
It is based on the transfer of electron between the titrant and the analyte, these type of titration are usually followed by potentiometry, although dyes which change colour when oxidised by excess titrant may be used.
Redox Titration
It is a type of chemical reaction that involves a transfer of electrons between two species.
Oxidation-Reduction Reaction / Redox Reaction
It is any chemical reaction in which the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron.
Oxidation-Reduction Reaction
Redox reactions are common and vital to some of the basic functions of life, including:
Photosynthesis
Respiration
Combustion
Corrosion or Rusting.
It is necessary to obtain an insight into electrode potentials.
Underlying Oxidation and Reduction Method of Analysis
The two species that exchange electrons in a redox reaction are:
Oxidizing Agent
Reducing Agent
The ion or molecule that accepts electrons.
By accepting electrons, it oxidizes other species.
Oxidizing Agent
The ion or molecule that donates electrons.
By giving electrons, it reduces the other species.
Reducing Agent
What is oxidized is the reducing agent and what is reduced is the oxidizing agent. (Note: the oxidizing and reducing agents can be the same element or compound, as in disproportionation reactions discussed below).
A good example of a redox reaction
Thermite Reaction
Iron atoms in ferric oxide lose (or give up) OO atoms to AlAl atoms, producing Al2O3Al2O3.
Thermite Reaction
It is a measure of how thermodynamically favourable it is for acompound to gain electrons.
Reduction Potential
It indicates that a compound is readily reduced and, consequently, is a strong oxidising agent
High Positive Value for a Reduction Potential
A substance with a higher reduction potential will oxidise one with a lower reduction potential.
It is the difference in potential between two substances and is approximately the potential difference which would be measured if the substances comprised two halves of an electrical cell.
REACTION POTENTIAL
It refers to the process of developing paper by allowing the solvent to travel up the paper.
Ascending Chroma
Organic and inorganic substances have been separated using both ascending and descending techniques.
It is used when developing paper is allowing the solvent to travel down the paper.
Descending Chroma
It is a combination of the two types of paper chromatography. The upper part of the ascending chromatography can be folded over a glass rod in this technique, allowing the ascending development to change into the descending after crossing the glass rod.
Ascending-Descending Chroma
A square or rectangular piece of paper is used in this. One of the corners receives the sample. The second development is carried out at a right angle to the first run. This type of chromatography can be performed with two solvent systems or with identical solvent systems in both directions.
Two-Dimensional Chroma
Radial development is used in this. This technique makes use of circular filter paper. The materials to be analyzed are then arranged in the centre. Following the drying of the spot, the paper is placed horizontally on the petri-dish containing the solvent, so that the tongue or wick is exposed. When the solvent front travels a sufficiently long distance, the components separate into concentric circular zones.
Radial Chroma
Other term for Radial Chromatography
Circular Chromatography
In Thin Layer Chromatography, the mixture of substances is separated into its components with the help of a glass plate coated with a very thin layer of adsorbent, such as
Silica Gel and Alumina
a technique used to separate and analyze mixtures of substances based on their different properties.
CHROMATOGRAPHY
is widely used in various fields such as chemistry, biochemistry, and environmental science.
CHROMATOGRAPHY
how much a substance is likely to be in either the mobile or stationary phase
Affinity
It is the flow of liquids in a confined space against the force of gravity.
Capillary Action
Polar substances have a high affinity for Polar solvents
The more polar substance had a lower retention factor than the less polar substance, because the stationary phase is more polar.
Low affinity for stationary phase =
travels through column quickly
High affinity for stationary phase = travels through column slowly
