Chapter 3 Study Guide: Matter, Mixtures, Elements, and Compounds

A comprehensive collection of vocabulary flashcards derived from the Chapter 3 Study Guide covering properties, changes, mixtures, elements, and chemical laws.

States of matter

The physical forms in which all matter naturally exists on Earth—most commonly solid, liquid, and gas.

Solid

A form of matter that has its own definite shape and volume.

Liquid

A form of matter that flows, has constant volume, and takes the shape of its container.

Gas

A form of matter that flows to conform to the shape of its container and fills the entire volume of its container.

Vapor

The gaseous state of a substance that is a solid or a liquid at room temperature.

Physical property

A characteristic of matter that can be observed or measured without changing the sample's composition.

Extensive property

A physical property that depends on the amount of substance present (such as mass, length, or volume).

Intensive property

A physical property that remains the same no matter how much of a substance is present (such as density, boiling point, or color).

Chemical property

The ability or inability of a substance to combine with or change into one or more other substances.

Physical change

A type of change that alters the physical properties of a substance but does not change its composition.

Phase change

A transition of matter from one state to another (such as melting, freezing, or evaporating).

Chemical change

A process that involves one or more substances changing into entirely new substances; also called a chemical reaction.

Law of conservation of mass

A law stating that mass is neither created nor destroyed during a chemical reaction—it is conserved.

Mixture

A physical combination of two or more pure substances in which each substance retains its individual chemical properties.

Heterogeneous mixture

A mixture that does not blend smoothly throughout and in which the individual substances remain distinct.

Homogeneous mixture

A mixture that has a constant composition throughout; it always has a single phase.

Solution

Another name for a homogeneous mixture, which can be a solid, liquid, or gas.

Filtration

A technique that uses a porous barrier to separate a solid from a liquid in a heterogeneous mixture.

Distillation

A physical separation technique that is based on differences in the boiling points of the substances involved.

Crystallization

A separation technique that results in the formation of pure solid particles of a substance from a solution containing the dissolved substance.

Sublimation

The energy-requiring process by which a solid changes directly to a gas without first becoming a liquid.

Chromatography

A technique that separates the components of a mixture dissolved in a gas or liquid based on the ability of each component to travel or to be drawn across the surface of a fixed substrate.

Element

A pure substance that cannot be broken down into simpler substances by physical or chemical means.

Periodic table

A chart that organizes all known elements into a grid of horizontal rows (periods) and vertical columns (groups or families) based on their increasing atomic number and repeating chemical properties.

Compound

A chemical combination of two or more different elements joined together in a fixed proportion.

Law of definite proportions

A law stating that a compound is always composed of the same elements in the same proportion by mass, no matter how large or small the sample.

Percent by mass

A percentage scale used to express compound composition, calculated by dividing the mass of an element by the total mass of the compound and multiplying by $100$.

Law of multiple proportions

A law stating that when different compounds are formed by a combination of the same elements, different masses of one element combine with the same fixed mass of the other element in a ratio of small whole numbers.