Elements, Compounds & Mixtures

These flashcards cover the key vocabulary and concepts related to the classification of substances in chemistry, including elements, compounds, mixtures, and various separation techniques.

Element

A substance made of atoms that all contain the same number of protons and cannot be split into anything simpler.

Compound

A pure substance made up of two or more elements chemically combined.

Mixture

A combination of two or more substances (elements and/or compounds) that are not chemically combined.

Pure Substance

A substance that consists of only one type of particle; it can be an element or a compound that contains no other substances.

Filtration

A physical separation technique that uses a filter to separate an undissolved solid from a liquid.

Crystallization

A separation technique used to separate a dissolved solid from a solution, where the solid is much more soluble in hot solvent than in cold.

Simple Distillation

A separation technique used to separate a liquid from a soluble solid or a pure liquid from a mixture of liquids.

Fractional Distillation

A separation technique used to separate two or more miscible liquids based on their different boiling points.

Chromatography

A technique used to separate substances that have different solubilities in a given solvent.

Rf value

The retention factor in chromatography, calculated as the distance moved by the substance divided by the distance moved by the solvent.