Chapter 3- Separation and Purification

Pure substance

A substance consists of a single element or compound.

Impurities

Cause variation in the melting and boiling points of the substance.

Ninhydrin

________) is sprayed on the chromatogram to make them visible.

Pure substances

Have a constant and fixed boiling and melting point.

RF value

Calculated by dividing the distance moved by the solute by the distance moved by the solvent.

Chromatography

A laboratory technique for the separation of a mixture.

Locating Agent

Used to analyze colourless substances in paper chromatography.

Simple distillation

Laboratory technique to separate pure solvent (liquid) from the solution.

Fractional distillation

Laboratory technique to separate miscible liquids with different boiling points.

Sublimation

A change directly from the solid to the gaseous state without becoming liquid.

Crystallization

To separate a pure solid from a solution.

Filtration

The process whereby fluids pass through a filter or a filtering medium.

Separating funnel

A piece of laboratory glassware used in liquid-liquid extractions to separate the components of a mixture into two immiscible solvent.