Matter can be classified as either pure substances or mixtures. Pure substances are either elements or compounds that have a definite and constant composition and properties under the same conditions. Mixtures have a varying composition and properties, and can be either homogeneous, consisting of a single phase mixed on a particle level, or heterogeneous, consisting of two or more phases. All living things are heterogeneous mixtures of different substances.

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Classification of Matter
Matter: has mass, occupies space
Pure substances
• Only 1 substance present
• Definite and constant
composition
• Same properties under
same conditions (ex: bp,
mp)
• Elements or compounds
Mixtures
• Physical combimation
• Varying composition and
properties
• Homogeneous – 1 phase
– Mixed on particle level – not
groups
• Heterogeneous – 2 or more
phases

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Examples
Of elements
Allotropes
C
O
P

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Heme – hemoglobin example
CO2 bound to protein chain – doesn’t directly compete with O2

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All living things are heterogeneous

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Molecular
Substances
Dissolve as
Molecules
Molecular
Substances
Are composed
Of non-metals
Ionic substances
Are composed of
Ions
Often a metal + non-metal
Or poly atomic ion
NaCl Na2SO4
Dissolve as individual ions
Electrolytes
Recurrent theme!!!

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Classification of matter