Classifying Matter
Matter
Are all the particles alike?
YES
NO
Pure Substance
Are the particles one
kind of atom?
YES
Element
NO
Compounds
or Molecules
Mixture
Are the particles well-mixed
and mixed evenly?
YES
NO
Homogeneous Heterogeneous
Mixture
Mixture
Pure Element,
Compound/Molecule,
or Mixture?
Conclusion for lab.
This way of categorizing
better, your way better, or both
are good and why??
Pure Substances
1. Elements
 all particles are alike
 the smallest particle of an element that is still
recognizable is called an atom
 they can’t be broken down anymore by “normal
means”
 they are found on the periodic table
currently
there are about 118 elements
chemical symbols are used to represent
the elements
• Example: C=carbon, N=nitrogen…..
2. Compounds and Molecules (over 10 million
exist)
two or more elements chemically combined
 once combined, the properties of a compound are
different than the elements that make it up
 can be broken down into the elements that make
them up
 example: Sugar is C6H12O6

made up of carbon, hydrogen, and oxygen
 looks nothing like C, H, O by themselves
 can be broken down when burned

Mixtures
1. Heterogeneous Mixture
 different samples are not necessarily made up
of exactly the same proportions of matter
 can often see different particles mixed
together
 often can be easily separated
2. Homogeneous Mixture
 is the same throughout
 often can’t see different particles mixed
together
 often difficult to separate
 examples: steel, milk, salt water, Kool Aid®
 History of the “Atomic Theory” video