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Observe through senses without changing the chemical
composition of the substance.
• Differences in physical properties make it possible to
separate out substances in a mixture.
Extensive • Depend on sample size or amount of substance present.
Properties Mass, volume and weight.
Intensive • Do not depend on sample size or amount present.
Properties
Melting point, freezing point, boiling point, density,
solubility, conductivity, hardness, color and odor.
Observe through interactions with other substances.
It reacts with, it burns with, it decomposes into, and it rusts.
A change that does not change the chemical composition of
a substance.
• No new substance is formed.
• Most are reversible.
Phase change H2O(l) H2O(s)
Dissolving NaCl(s) NaCl(aq)
A change that will alter the chemical composition of a
substance through a chemical reaction.
• New substances (with different sets of properties) are
always produced.
• Most are irreversible.
Synthesis 3H2 + 2N2 2NH3
Decomposition 2H2O 2H2 + O2
Single Replacement Mg + 2HCl MgCl2 + H 2
after a change Chemical Physical
Change Change
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