Analytical Chemistry: Analytical Separations and Chromatography

These flashcards cover key concepts and vocabulary from the lecture on analytical separations and chromatography methods within analytical chemistry.

Analyte

The substance whose chemical constituents are being identified and measured.

Solvent Extraction

A separation technique that transfers a solute from one phase to another based on solubility differences.

Chromatography

A method for separating components in a mixture based on differential partitioning between a stationary phase and a mobile phase.

Partition Coefficient (K)

The ratio of concentrations of a solute in two phase systems at equilibrium.

Electrophoresis

A separation technique that utilizes an electric field to move charged particles through a medium.

Field-Flow Fractionation

A separation method based on the differential migration of particles under the influence of an external field.

Immiscible Solvents

Solvents that do not mix together, leading to the formation of separate layers.

Retention Time (tr)

The time it takes for an analyte to pass through the chromatographic column to the detector.

Adjusted Retention Time (tr')

The retention time of an analyte minus the marker time for unretained solutes.

Capacity Factor (k')

The ratio reflecting how long an analyte is retained in the stationary phase compared to the mobile phase.

Selectivity Factor (α)

The ratio of retention times of two analytes, indicating their separation potential.

Resolution (Rs)

The ability to distinguish two separate peaks in a chromatogram.

Hydrogen Bonding

A strong dipole-dipole attraction between molecules where a hydrogen atom is attached to a highly electronegative atom.

Ion Exchange

A separation technique that involves swapping ions from a solution with ions from a solid resin.

Normal Phase Chromatography

A chromatographic technique where the stationary phase is polar and the mobile phase is less polar.

Reversed-Phase Chromatography

A chromatographic technique where the stationary phase is non-polar and the mobile phase is polar.

Dispersion Forces

Weak intermolecular forces arising from temporary shifts in electron density in molecules.