chaptertwo1

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Chapter Two: Matter and Change
Properties of Matter
If you had to describe matter, what would you say?
Describing Matter
 PROPERTIES USED TO DESCRIBE MATTER CAN BE
CLASSIFIED AS EXTENSIVE OR INTENSIVE
 Extensive properties include:
 The mass of the object
 The volume of the object
 It depends on the amount of matter in a sample
 Intensive properties include:
 Hardness
 Smoothness
 Depends on the type of matter in a sample
 Ex. All samples of pure gold have identical intensive
properties because their chemical composition is identical.
Identifying Substances
 Matter that has uniform and definite composition is

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
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called a substance
EVERY SAMPLE OF A GIVEN SUBSTANCE HAS
IDENTICAL INTENSIVE PROPERTIES BECAUSE
EVERY SAMPLE HAS THE SAME COMPOSITION
Examples of physical properties include:
Hardness, boiling point, freezing point, colour,
conductivity, malleability
Physical properties can be observed and measured
without changing the substance's composition
Copper vs. Gold
How are they different/same?
Page 40, Table 2.1
States of Matter
 THREE STATES OF MATTER ARE SOLIDS, LIQUIDS
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AND GASES
Solids have definite shape, volume and not easily
compressed
Liquids have indefinite shape, definite volume and
not easily compressed
Gases have indefinite shape, indefinite volume, and
are easily compressed
The particles composing each varies from state to state
See Figure 2.3 on page 41
Physical Changes
 During a physical change, some properties of the
material changes, but the composition does not
 What are some words that could be used to describe
physical changes of a substance?
 Look at Figure 2.4, and answer the questions – Is the
melting of gallium a reversible or irreversible change?
What is the physical state of gallium at room
temperature?
Mixtures
 A mixture is a physical blend of two or more
components
 BASED ON THE DISTRIBUTION OF THEIR
COMPONENTS, MIXTURES CAN BE CLASSIFIED AS
HETEROGENEOUS MIXTURES OR AS
HOMOGENEOUS MIXTURES
 Heterogeneous mixtures do not have uniform
composition (trail mix). Each part is called a phase.
 Homogeneous mixtures, or solutions, have uniform
composition (stainless steel). By definition, they have
one phase.
Separating Matter
 DIFFERENCES IN PHYSICAL PROPERTIES CAN BE
USED TO SEPARATE MIXTURES
 Floating, freezing, filtration, distillation, using magnets,
etc.
Check for comprehension:
Questions 1 -8, pg. 42
Questions 9-10, pg. 46
Questions 11 – 17, pg. 47
Guided reading, sections 2.1, 2.2
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