Ch 08 - Nature of Matter: Elements, Compounds, and Mixtures8th Science

Definition: Matter is anything that possesses mass and physically occupies space (volume).

Building Blocks: All macroscopic matter is constructed from extremely tiny, discrete, and indivisible constituent particles, such as atoms and molecules.

Note: In our daily environment, most materials are not single, pure substances but are complex mixtures of two or more different substances.

Daily Life: 'Pure' simply means unadulterated or unmixed with cheaper/harmful additives (e.g., 'pure milk', which is actually a complex mixture of water, fats, and proteins).

In Science: A pure substance must be constructed of only one single kind of constituent particle (either entirely one type of atom or entirely one type of molecule) and possess a fixed, invariable chemical composition.

Key Property: A scientifically pure substance absolutely cannot be separated into other kinds of matter by simple physical methods (like filtration or boiling).

Element: It is the absolute simplest form of a pure substance. It cannot be broken down into any simpler substances by any known chemical or physical means.

Atom: The atom is the smallest, most fundamental constituent particle of an element.

The Relationship: A specific element is constructed entirely of identical particles (atoms). The atoms of one particular element (e.g., Gold) are fundamentally different in structure and mass from the atoms of any other element (e.g., Iron).