Download Properties of Matter

Properties of Matter
What is matter?
Matter is anything that has
mass and volume.
Classification of Matter
Matter can be divided into 2 categories:
SUBSTANCES & MIXTURES
• Substances can NOT be separated into
different kinds of matter by physical means.
• Mixtures can be separated into different
kinds of matter by physical means.
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Classification of Matter
What are substances?
In science, substances are limited to elements
and compounds.
– Elements
• Any substance in which all the atoms in a
sample are alike, one kind of matter
• Examples: Carbon, Sodium and Oxygen
– Compounds
• 2 or more elements chemically
combined in a fixed ratio
• Usually has different appearance from
elements that make it up
• Examples: Water – H2O and Salt - NaCl
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Classification of Matter
• Atom-smallest
possible particle of
an element
• Molecule- smallest
possible particle of
a compound
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Classification of Matter
What are mixtures?
2 or more substances that can be separated by
physical means
Do not always contain the same amounts of the
different substances that make them up
–Homogeneous
• same throughout, particles so tiny that cannot
be seen, don’t settle out or scatter light
• Examples: milk, salt water and cola
–Heterogeneous
• a mixture in which different materials can be
easily distinguished
•Suspension-visible particles settle-muddy water
• Examples: Sand/water, Italian salad dressing,
pizza and dry soups
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Classification of Matter
MATTER
Has mass and
takes up space.
SUBSTANCES
Definite Composition
ELEMENT
Only 1 Kind
of Atom
COMPOUND
Two or More
Kinds of
Atoms
MIXTURES
Variable Composition
HOMOGENEOUS
Solution evenly
mixed
HETEROGENEOUS
Solution
Unevenly mixed
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Measuring Matter
Volume of a liquid
– Graduated cylinder- read from bottom of
meniscus
Volume of solid
– Length X Width X Height
Volume of Irregular Shaped Objects
– Water Displacement
Indirect Measuring
– Large objects-take a core sample and use a
formula
– Small objects-weigh 100 and then divide weight
by 100 to get one small objects weight
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Phases & Properties of Matter
What is the matter?
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Phases of Matter
Solids - definite shape and volume
Atoms are held close together by strong bonds
 Movement is slow
 Crystalline Solids (crystals) - atoms are
arranged in regular fashion
• Ex. - ice, salt, diamonds


Amorphous Solids - atoms LACK a regular
arrangement
• Ex. - rock, glass, wax
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Phases of Matter - Continued
Liquids - definite volume, but NO definite
shape
Bonds are weaker and atoms are spaced
farther apart
 They take the shape of container they
are in

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Phases of Matter - Continued
Gases - NO definite volume OR shape

Bonds are weakest and atoms far apart

Expand to fill the container they are in
• Examples - air, oxygen, smoke
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Phases of Matter - Continued
Plasma
• Gas like mixture of + and – charged particles

Movement very rapid

99% of mass of our solar system

Examples: Sun, Stars and Lightning
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Physical Properties of Matter
• Viscosity –


• Measure of the material’s resistance to flow
• High-viscosity liquids take longer to flow
• Example: Ketchup when comparing to
water
• Low-viscosity liquids flow easier
• Example: Tomato Juice flows
easier than ketchup
• Temperature raising-viscosity decreases
except in gases.
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Physical Properties of Matter – Cont.
• Elasticity –
• Measure of ability to be stretched and
then return to its original size.
• Example:Rubber Bands, Elastic, and
Playground Balls
Question: Which ball would you rather play
basketball?
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Physical Properties of Matter – Cont.
• Malleability –
• Ability to be hammered into sheets
• Example: Gold &Silver Coins, Aluminum
Foil and Soda Cans
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Physical Properties of Matter – Cont.
• Brittleness –
• measures a material’s tendency to
shatter upon impact
• Example: Sulfur, Calcium and Glass
• Hardness –
• Resistance to breaking or scratching
• Example: diamonds
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Physical Properties of Matter – Cont.
• Luster –
• shininess
• Example: Gold, Silver, Mercury
• Ductility –
• ability to be pulled into wires
• Example: Most metals (Copper, Silver)
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Physical Properties of Matter – Cont.
Tensile Strength• Measure of how much
pulling, or tension, a
material can withstand
before breaking
• Property of fibers,
ropes, cables, girders
• DuPont Kevlar-5 times
tensile strength of steel
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Physical Properties of Matter – Cont.
• Density –
• The amount of mass in a given volume
• How tightly packed the atoms or molecules
are in a substance
• Formula to calculate density is:
Density = Mass
Volume
• Units are expressed as:
• g/mL or g/L for liquids (remember the graduated
cylinder)
• g/cm3 for solids
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Density of a Fluid
Fluid• Any matter that is able to flow
• Liquids and gases
• Density of a liquid might be different from the
density of the same solid
• Most materials are denser in solid phase
than their liquid phase
• Exception- Water-freezes with air spaces so
it is less dense and floats.
• Density of water is 1 g/cm3
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Physical Properties of Matter – Cont.
• Buoyancy –
• Upward force a fluid exerts on an object
•Determines whether the object will sink
or float
• Example: Buoyancy of water keeping
you afloat while swimming
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Buoyancy
Buoyancy force is LESS
then object’s weight,
object will SINK
Buoyancy force is equal
to the object’s weight,
object will FLOAT
Buoyancy force is
MORE then object’s
weight, object will
FLOAT IN AIR
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Archimedes's Principle
• Greek mathematician, 3rd century BC
• Principle states-The buoyancy force on an object in a
fluid is equal to the weight of the fluid displaced by the
object
Buoyancy of Gasses
• Balloon floats because it displaces a very large
volume of air
• Volume of air displaced weighs more than the balloon
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Charles’ Law
Jacques Charles, French scientist (17421823)
• Law states-volume of a gas increases
when temperature increases and
reverse, volume of gas decreases
when temperature decreases.
• Pascal-unit for pressure (Pa) (kPa)
• V1 / T1 = V2 / T2
– Temperature must be in Kelvin degrees
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Boyle’s Law
Robert Boyle-British scientist (1627-1691)
• Law states-as pressure of a gas
increases, its volume decreases
proportionately and reverse pressure of
gas decreases, its volume increases
proportionately.
• P1 V1 = P2 V2
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