Properties used to describe matter can be classified as extensive or intensive.

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Describing Matter

• Properties used to describe matter can be
  classified as extensive or intensive.
• An extensive property is a property that depends
  on the amount of matter in a sample.
• An intensive property is a property that depends
  on the type of matter in a sample, not the amount
  of matter.

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Describing Matter
2.1

• Extensive properties depend on amount.
• The mass of an object is a measure of the amount
  of matter the object contains.
• The volume of an object is a measure of the space
  occupied by the object.

The big ball has more mass and volume than the
little ball.
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Describing Matter
2.1

• Intensive Properties
• The hardness of a bowling ball is an example of
  an intensive property.

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Is flammability an extensive or intensive
property?
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Identifying Substances
2.1

• Matter that has a uniform and definite
  composition is called a substance.
• A substance is pure.

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Identifying Substances
2.1

• Every sample of a given substance has identical
  intensive properties because every sample has the
  same composition.
• Example- Every sample of pure water is a clear,
  odorless, liquid at room temperature. The water
  will boil at 100ºC and freeze at 0ºC. These
  properties are intensive because they do not
  depend on how big the sample is.

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Identifying Substances
2.1

• A physical property is a quality or condition of
  a substance that can be observed or measured
  without changing the substances composition.
• Hardness, color, conductivity, and malleability
  are examples of physical properties.

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Identifying Substances
2.1
9
States of Matter
2.1

• What are three states of matter?
• Three states of matter are solid, liquid, and
  gas.

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States of Matter
2.1

• Solids
• A solid is a form of matter that has a definite
  shape and volume.

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States of Matter
2.1

• Liquid
• A liquid is a form of matter that has an
  indefinite shape, flows, yet has a fixed volume.

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States of Matter
2.1

• Gases
• A gas is a form of matter that takes both the
  shape and volume of its container.
• The gas state is the only state of matter that is
  compressible.

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States of Matter
2.1

• Vapor describes the gaseous state of a substance
  that is generally a liquid or solid at room
  temperature, as in water vapor.

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States of Matter

• Macroscopic qualities- volume, shape, and
  compressibility
• Microscopic properties- Relate the states of
  matter to the arrangements of their particles.

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States of matter- the 3 forms at which matter
exists
Solid- particles are tightly packed in a rigid
structure. Has a shape and a fixed volume!
Liquid- particles are very close but can move
around each other. Takes the shape of its
container, but has a fixed volume.
Gas- particles are far apart and have little
effect on each other. Has no fixed shape or
volume.  
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Substances go from solid to liquid to gas as
energy increases.
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Physical Changes
2.1

• During a physical change, some properties of a
  material change, but the composition of the
  material does not change.
• As gallium melts in a persons hand, the shape of
  the sample changes, but the composition of the
  material does not change.

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Physical Changes
2.1

• Physical changes can be classified as reversible
  or irreversible.
• All physical changes that involve a change from
  one state to another are reversible.
• Cutting hair, filing nails, and cracking an egg
  are examples of irreversible physical changes.

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2.1 Section Quiz.

• 1.Which of the following would be described as an
  extensive property of matter?
• temperature
• color
• mass
• hardness

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2.1 Section Quiz.

• 2. Which properties can be observed without
  changing the composition of a substance?
• all properties of a substance
• intensive properties
• chemical properties
• physical properties

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2.1 Section Quiz.

• 3. Match the states of matter with the following
  descriptions
• (1) takes the volume and shape of its container
• (2) has a definite shape and volume
• (3) has a definite volume but an indefinite shape
  
• (1) liquid, (2) solid and (3) gas
• (1) gas, (2) solid, and (3) liquid
• (1) gas, (2) liquid, and (3) solid