PS03-3 Classifying Matter

Pure substances -- have a distinct composition that is always the same

Mixtures -- a physical blend of two or more substances with properties that vary from one mixture to the next.

Pure substances are sometimes referred to as "homogeneous" too, but they are NOT mixtures.

Made up of only one type of element

Easy to figure out because there's a chart of them! (The Periodic Table!)

Represented by a 1 or 2 letter symbol where first letter is always capitalized.

Elements cannot be broken down any further, neither by physical nor chemical means.

Mixtures vary in composition from one sample to another.

Think of Sweet Tea or Soda. If you buy it at different times or different places, it might taste a little different due to different amounts of sugar.

Mixtures are physical blends of two or more compounds.

Mixtures can be separated by physical means.

Consist of one phase throughout

Also called "solutions"

Can be solid (12K gold), liquid (salt water) or gaseous (air)

Not separated by filtration or upon standing

Consist of more than one phase

Can be further divided into colloids (do not settle) and suspensions (settle on standing)

Can be solid (sand), liquid (orange juice) or gaseous (fog sort of)

TIP: "Hetero-" means 'different'