Chemistry Unit 2.2

Homogeneous mixture

A combination of two or more substances that cannot be distinguished from each other. It has uniform composition and properties.

Heterogeneous mixture

A combination of two or more substances that can be distinguished from each other. It has varying composition and properties.

Evaporation

The phase transition of matter from liquid to vapor. It is a separation technique used for solid-liquid mixtures where a solid solute is dissolved in a liquid solvent.

Recrystallization

A separation technique based on the difference in solubilities of substances in an appropriate solvent at an elevated temperature. It is often used as a purification technique for solid mixtures.

Distillation

A separation technique used for homogeneous liquid-liquid mixtures based on the difference in boiling points between the two liquid components.

Chromatography

A separation technique that relies on the differential partition of components between the mobile phase and the stationary phase. It can be classified based on the polarity of its phases or the structure of the stationary phase.

Manual separation

A separation technique for heterogeneous mixtures with large, visible components that involves picking the components individually or using sieving or a magnet.

Filtration

A process of separating solids from liquids by allowing the mixture to pass through a filtering material. It is used for solid-liquid suspensions and colloids.

Sedimentation

The process in which suspended solids separate from liquids by gravity. It is followed by decantation, which is the removal of the liquid component from solid sediment.

Centrifugation

A process in which a suspension or colloid is rotated at high speeds to separate the solid particles from the liquid. It is often used for small dispersed particles that do not settle easily.