Table of Contents
Can mobile phase be liquid?
The mobile phase may be either a liquid or a gas, while the stationary phase is either a solid or a liquid.
What determines the movement of solute if the mobile phase is gas?
Explanation: If the mobile phase is gas, movement of solute is determined by its volatility because gas is always measured as volatility not as solubility or melting point or boiling point.
What does the mobile phase do in chromatography?
Phases. Chromatography relies on two different ‘phases’: the mobile phase is the solvent that moves through the paper, carrying different substances with it. the stationary phase is contained on the paper and does not move through it.
What is mobile phase composition?
Mobile phases are of binary solvents (normally methanol and water) and the elution is done isocratically or with a linear gradient. From: Encyclopedia of Separation Science, 2000.
Why is water the mobile phase?
Pure water in elevated temperature can be used as mobile phase in liquid chromatography mainly due to change of dielectric constant. Water dielectric constant is reduced from 85 at 25°C to 35 at 200°C cause that water behave like an organic solvent.
What is a mobile phase?
Mobile-phase meaning Filters. (chemistry) The liquid or gas that flows through a chromatography system, moving the materials to be separated at different rates over the stationary phase. noun.
What makes a good mobile phase in chromatography?
Mobile phase components should be non-hazardous and non-toxic. They should not pose any health hazard to the operator. Mobile phase shouId be inert towards sample constituents and the stationary phase. Any reactions can lead to formation of insoluble suspensions which can result in column blockages.
What is the rate theory of chromatography?
The rate theory provides a more realistic explanation of the processes that take place inside a chromatographic column. It takes into account the time taken by the solute to equilibrate between the stationary and mobile phase unlike the plate model which assumes that the equilibration is infinitely fast.
What factors determine the rate of migration of a solute in paper chromatography?
The size and shape of a molecule also influence the rate of migration in that the larger the size, the slower the molecule will move in electrophoresis. The viscosity and the pore size in the support media or gels used for electrophoresis influence the rate of migration.
What role does the mobile phase play in the distance a molecule travels in chromatography?
What role does the mobile phase play in the distance a molecule travels in chromatography? The molecule phase displays the solvent used in chromatography. The mobile phase flows through the paper, carrying the components of the mixture with it.
What do you mean by mobile phase and stationary phase in chromatography?
In all chromatography there is a mobile phase and a stationary phase. The stationary phase is the phase that doesn’t move and the mobile phase is the phase that does move. In paper and thin-layer chromatography the mobile phase is the solvent.
Which is the mobile phase of liquid chromatography?
Liquid chromatography (includes column chromatography, thin-layer, and HPLC) – Stationary phase: silica, alumina, etc. – Mobile phase (moving phase): organic solvents – Important properties: polarity. Gas chromatography. – Stationary phase: a film of a polymer or a wax.
How is a sample dissolved in a mobile phase?
Sample is dissolved in a mobile phase (a gas, a liquid or a supercritical fluid); The mobile phase is forced through an immiscible stationary phase which is fixed in place in a column or on a solid surface.
Which is an example of a mobile phase?
Some examples of solvents used as mobile phase based on their polarity are – ethanol, acetone, water, acetic acid, pyridine, etc. Stationary phase – It is a solid material which should have good adsorption property and meet the conditions given below:
What makes components move faster in column chromatography?
The components with lower adsorption and affinity to stationary phase travel faster when compared to the greater adsorption and affinity with the stationary phase. The components that move fast are removed first whereas the components that move slowly are eluted out last.