Chemistry 1-1

Matter

Anything that has mass and takes up space (volume).

Mixtures

Combinations of two or more substances in which each substance retains its own chemical identity.

Homogeneous

Matter that consists of a single phase and has uniform properties throughout.

Heterogeneous mixture

Matter with more than one phase, where the composition and properties vary throughout.

Phase

A region of matter with a uniform set of properties.

Pure substances

Substances that cannot be separated into simpler components by physical changes.

Physical changes

Changes that alter the physical appearance of a substance but not its composition.

Solutions

Homogeneous mixtures commonly referred to, where substances are uniformly distributed.

Solute

The substance that is dissolved in a solution.

Solvent

The substance that dissolves the solute in a solution.

Aqueous solution

A solution in which water is the solvent.

Distillation

A process used to separate the components of a mixture based on their boiling points.

Physical properties

Properties that can be measured without changing the composition of a substance.

Chemical properties

Properties that describe how a substance may change or react to form new substances.

Extensive properties

Properties that depend on the amount of substance, such as mass and volume.

Intensive properties

Properties that do not depend on the amount of substance, such as density.

Compound

A substance that can be separated into simpler substances by chemical changes.

Element

A basic building block of matter that cannot be broken down by chemical changes.

Metals

Elements characterized by shiny luster, high electrical and thermal conductivities, malleability, and ductility.

Nonmetals

Elements that are not lustrous, poor conductors, and have lower melting points than metals.

Metalloids

Elements that have properties intermediate between metals and nonmetals, such as silicon.