Chapter 1 - Matter and Change

classification of matter

matter can exist in three forms or phases: solids, liquids, or gases.

mixtures

a mixture is a material made up of two or more different chemical substances which are not chemically bonded (physical combinations)

pure substances

A substance that has a fixed chemical composition throughout such as water, air, and nitrogen. A pure substance does not have to be of a single element or compound.

elements

refers to a simple substance that cannot be broken down into smaller parts or changed into another substance

compounds

A chemical compound is a chemical substance composed of many identical molecules containing atoms from more than one chemical element held together by chemical bonds

states of matter

one of the distinct forms in which matter can exist. Four states of matter are observable in everyday life: solid, liquid, gas, and plasma.

chemical properties

any of a material's properties that becomes evident during, or after, a chemical reaction; that is, any quality that can be established only by changing a substance's chemical identity.

physical properties

any property that is measurable, whose value describes a state of a physical system. The changes in the physical properties of a system can be used to describe its changes between momentary states

physical change

A change in matter which does not alter the chemical properties of the matter

chemical change

are not reversible except by further chemical reactions.