Matter, Elements, Compounds, and Mixtures

Vocabulary flashcards covering matter, its states, elements, compounds, mixtures, and related concepts discussed in the lecture.

Matter

Anything that has mass and takes up space.

Mass

A measure of the amount of matter in an object.

Volume

The amount of space that matter occupies.

States of matter

The three classical forms—solids, liquids, and gases—determined by particle energy and interparticle forces.

Solids

States with strong interparticle forces that lock particles into a rigid, often crystalline structure.

Liquids

States with moderately strong forces; particles slide past each other, giving fluidity; definite volume, indefinite shape.

Gases

States with very weak interparticle forces; particles move independently, fill the volume available, and are highly compressible.

Crystalline lattice

A highly ordered arrangement of atoms in a solid (example: diamond) that yields a rigid structure.

Atomic number

The number of protons in an atom's nucleus; defines the identity of the element.

Element

A fundamental substance that cannot be decomposed into simpler substances by ordinary chemical means.

Molecule

Two or more atoms bonded together; the basic unit of many substances.

Compound

Two or more different elements chemically bonded in fixed proportions, with properties different from its constituent elements.

Fixed proportions

In a compound, the constituent elements combine in specific, fixed ratios.

Emergent property

A new property or identity that arises when elements form a compound, not present in the elements alone.

Water (H2O)

A compound formed from hydrogen and oxygen; its properties differ from the individual elements.

Pure substance

Contains only one type of element or one type of compound; uniform composition.

Mixture

Two or more elements or compounds physically blended; components retain identities and can often be separated by physical means.

Homogeneous mixture

A uniform mixture (solution) where components are not visually distinguishable; examples include sugar in water and air.

Heterogeneous mixture

A non-uniform mixture with visibly distinct components, such as salad dressing or concrete.

Solution

A homogeneous mixture where a solute is dissolved in a solvent.

Physical separation

Separating mixtures by physical means (filtration, evaporation, magnets) without changing chemical identity.

Chemical separation

Breaking down compounds into elements or simpler compounds by chemical reactions (e.g., electrolysis).