Classification of Matter

Pure Substances Have specific properties that identify it (physical or chemical) Can be elements or compounds

Elements Substances with only one kind of atom Can be monatomic (Na, B) or in molecules (O2 or O3 or N2) May have more than one form called allotropes– ex O2 and O3

Allotropes of C

Periodic Table

Pure Substances cont’d Compounds- composed of more than one kind of atom Have definite composition Properties are different than those of the individual elements Are represented by formulas Ex H2O2, symbols represent the elements and subscripts give the number of atoms of that element in the compound

Mixtures Composed of two or more pure substances Each component retains it’s properties Can use those properties to separate components Homogenous- substances evenly distributed Solution, alloy Heterogeneous- not evenly distributed Suspension, colloid