Pure Substances & Mixtures

heterogeneous mixture

a combination of substances in which different components are easily observed

homogeneous mixture

a combination of substances in which the appearance and properties are the same throughout

molecule

a combination of two or more atoms that are combined in a definite ratio

mixture

a combination of two or more substances that are not chemically combined

solution

a mixture that appears to be a single substance but is composed of particles of two or more substances that are distributed evenly amongst each other

pure substance

a substance in which there is only one type of particle; includes elements and compounds

chemical formula

code that uses chemical symbols and subscripts to identify the types and numbers of atoms in a compound

compound

combination of substances (elements) that are chemically combined (bonded)

coefficient

in a chemical formula, the large number in front that tells how many molecules are present

subscript

in a chemical formula, the small number that identifies how many atoms of each type are in a molecule

law of conservation of matter

matter cannot be created or destroyed, it can only change from one form to another

chemical symbol

one or two letter code that represents an element; derived from the Latin name for an element

solvent

the substance in which a solute is dissolved to form a solution

solute

the substance that is dissolved to form a solution

reactant

the substances that exist before a reaction occurs (ingredients)

product

the substances that remain after a reaction takes place (resulting molecules)