Describing Matter The mass of an object is a measure of the amount of matter the object contains.

Describing Matter The volume of an object is a measure of the space occupied by an object.

States of Matter

Identifying Substances Matter that has a uniform and definite composition is called a substance.

Elements and Compounds An element is the simplest form of matter that has unique properties.

Elements and Compounds A compound is a substance that contains two or more elements.

Classifying Mixtures A mixture is a physical blend of two or more components.

Classifying Mixtures A homogeneous mixture is a mixture with a uniform composition. A heterogeneous mixture is a mixture with a variable composition.

Physical Properties A physical property can be observed or measured without changing a substance’s compsotion.

Physical Changes During a physical change, some properties of a material change, but the composition does not change.

Phase Changes

Solid-Liquid Changes Solid  Liquid is called melting. Liquid  Solid is called freezing

Liquid-Gas Changes Liquid  Gas is called boiling. Gas  Liquid is called condensation.

Solid-Gas Changes Solid  Gas is called sublimation. Gas  Solid is called deposition.

Phase Changes

Chemical Changes The ability of a substance to undergo a specific chemical change is called a chemical property.

Chemical Changes A chemical change produces matter with a different composition than the original matter.

Chemical Changes One or more substances change into one or more new substances during a chemical reaction. + 

Recognizing Chemical Changes Production of a gas Color Change

Recognizing Chemical Changes A precipitate is a solid that forms and settles out of a liquid mixture.

Recognizing Chemical Changes The law of conservation of mass states that in any physical change or chemical reaction, mass is conserved.