Matter, Phase Changes, and Separation Techniques

Vocabulary flashcards covering mixtures, states of matter, Kinetic Molecular Theory, phase changes, heating curves, and laboratory separation techniques.

Heterogeneous Mixture

A mixture with different visible parts (such as milk, oil in water, or dirt in water) whose components can be separated by mechanical means such as picking, settling, straining, or centrifugation.

Colloid

A mixture containing particles between $1\,\text{nm}$ and $1\,\mu\text{m}$ dispersed throughout a continuous medium, formed by aggregates of molecules invisible to the eye that remain suspended indefinitely unless centrifuged or coagulated.

Tyndall Effect

The scattering of light caused by particles in a colloid that are large enough to make a bright beam of light visible when shone through the mixture.

Suspension

A coarse mixture with visible layers in which dispersed particles settle out or sediment upon standing.

Kinetic Molecular Theory (KMT)

A scientific explanation of the behavior of matter stating that all matter is made of small particles in constant random motion, where added energy causes particles to move faster and spread further apart.

Particles in a Solid

Particles that vibrate in place without moving around and attract one another strongly in a rigid structure, giving solids their own shape and a constant volume.

Particles in a Liquid

Particles that are very close together and slip and slide past one another with weaker attractive forces than solids, allowing liquids to take the shape of their container while retaining a constant volume.

Particles in a Gas

Particles that are very far apart compared to their size, move rapidly and randomly in straight lines, have zero attraction to one another, and can be compressed to take the shape and volume of their container.

Sublimation

The phase change in which a substance transitions directly from a solid to a gas without passing through the liquid state.

Deposition

The phase change in which a substance transitions directly from a gas to a solid without passing through the liquid state.

Heating Curve

A graph showing how the temperature of a substance changes as heat is added at constant pressure, illustrating phase transitions where temperature remains constant as kinetic energy is converted to potential energy to loosen or break bonds.

Total Energy ($\text{Total } E$)

The sum of kinetic energy and potential energy within matter, expressed as $\text{Total } E = KE + PE$, where temperature measures only kinetic energy.

Filtration

A separation method that separates an undissolved solid from a liquid using filter paper, relying on differences in particle size.

Residue

The solid material that is trapped and left behind on the filter paper during filtration.

Filtrate

The liquid that passes through the filter paper during filtration.

Evaporation (Separation Method)

A technique used to recover a dissolved solid from a liquid solution by heating the liquid until it evaporates, utilizing differences in boiling points and kinetic energy.

Distillation

A technique used to separate liquids without losing vapor into the air by boiling the component with the lowest boiling point first and condensing its gas back into a liquid via a condenser.

Density Separation

A technique used to separate mechanical mixtures based on differences in density by allowing layers to form and decanting them layer-by-layer or by using a centrifuge.

Chromatography

A method used to separate dissolved substances based on their relative affinities for a moving mobile phase and a stationary phase.

Mobile Phase

The moving liquid or gas component in chromatography that carries dissolved substances across the stationary medium.

Stationary Phase

The non-moving solid component in chromatography that retards the movement of substances based on attraction.

$R_f$ Value

The retention factor used in chromatography for compound identification, calculated as the distance traveled by the compound divided by the distance traveled by the solvent front.