Properties of Matter

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Matter
What is Matter?
Section 2.1
Matter
• Matter is what the
world is made of.
• Matter has mass
and volume
• All objects
consists of matter.
Mass
• A measure of the quantity of
matter in an object
• Measured by grams (g) and
kilograms (kg)
• Doesn’t change due to location
Weight
• Weight is the response of
mass to the pull of gravity.
Metric unit of weight is the
Newton (N).
• Does change due to location
Mass vs. Weight
• Weight = mass x acceleration
of gravity
• Mass kg X 9.8 m/s2 = Weight
(on earth) N
• What is your weight on earth?
(Remember 1 kg = 2.2 lbs)
What is your weight on
earth?
• mass X 9.8 m/s2 = Weight (on
earth)
• (Remember 1 kg = 2.2 lbs)
Volume
• The amount of space an object
takes up is called its volume.
• Volume is measured in liters
(L), milliliters (mL), and cubic
centimeters (cm3)
Chemistry
• The study of matter and how
it changes
Element
• A substance that cannot be
broken down into simpler
substances
• Everything
is made of
elements
Atom
• Smallest particle of an element
• Has all the properties of that
element
• Unique
Molecule
• Smallest unit of a compound
that exhibits all the properties
and characteristic of that
compound
 Element
•a substance that cannot be
broken down into simpler
substances
Compound
• A substance
made of atoms
of more than
one element
bound together
2.6 Earth's Composition
Earth’s
Composition
1.9
1.1
2.4
Iron
12.7
34.6
Oxygen
Silicon
Magnesium
Nickel
15.2
Sulfur
Calcium
All other elements
29.5
Chemical Formula
• Chemical symbols and numbers
indicating the atoms contained in
the basic unit of a substance
• A formula that represents one
molecule of a compound
• Empirical formula is the simplest
formula of a compound
• Molecular formula is a simple
multiple of its empirical formula
Elements in the Human Body
Elements in the Human Body
0.40%
0.30%
0.20%
1%
0.90%
1.60%
2.40%
10.20%
Oxygen
Carbon
Hydrogen
Nitrogen
Calcium
Phosphorus
17.50%
Potassium
65%
Sodium
Sulfur
All other element
Chemical Formula
• Examples
 C16H10N2O2
Indigo
 C12H22O11
Sugar
Classifying Matter
Classifying Matter
Classifying Matter
Classifying Matter
Classifying Matter
Classifying Matter
Classification of Matter
Pure Substance
• Any matter that has a fixed
composition and definite
properties
Mixture
• A combination of more than
one pure substance
• Blending together of pure
substances
Mixture
• Homogeneous
 Same kind
 Uniform in
structure or
composition
throughout
Mixture
• Heterogeneous
 Different kinds
 Not complete
mixed
 Consists of
dissimilar elements
or parts
Marble
Mixtures
• Miscible
 Able to dissolve into each other
in various proportions
Mixtures
• Immiscible
 describes two or
more liquids that
do not mix into
each other
Oil and Water
Platform Holly Oil Spill
November 1981
Matter
Matter and
Energy
Section 2.2
Matter and Energy
1. Think about the properties of ice. It
is somewhat hard and cannot be
compressed easily. Which drawing do
you think represents a solid? Why?
Matter and Energy
2. Think about the properties of
gases. They are not hard, and
they can be compressed. Which
drawing represents a gas? Why?
Matter and Energy
3. In which state(s) of matter
are the particles touching?
Matter and Energy
4. In which drawing do you think
the particles have the least effect
on one another? Why?
Kinetic Theory
• All matter is made up of atoms
and molecules that act like tiny
particles
• Tiny particles are always in motion.
The higher the temperature the
faster they move
• At the same temperature heavier
particles move slower than lighter
particles
States of Matter
• Four phases of matter
 Solid
 Liquid
 Gas
 Plasma
Gases
• Do not have a regular shape
• Nor a regular volume
• Take on the shape of their
container
Particles of a Gas
• Move fast enough
to overcome nearly
all of the attraction
between them
• The particles move
independently of
one another
Gas
Pressure
• Force exerted
per unit area
on a surface
•P = F / A
Pressure
• Gas particles exert
pressure by hitting
the walls of a
balloon.
• The balloon pops
because the
internal pressure is
more than the
balloon can hold.
Liquids
• Have a definite volume
• Do not have a definite shape
• Take on the shape of their
container
• Viscosity
 The resistance of a liquid to flow
Particles of a Liquid
• Move fast enough
to overcome some
of the attraction
between them
• The particles are
able to slide past
one another
Liquid
Solids
• definite shape
• definite volume
• Crystalline Solids
 In many solids, the particles are
arranged in a regular, repeating
pattern called a crystal. (i.e.
salt, quartz)
Crystals
Solids
• Amorphous solids
 lose their shape under certain
conditions
•(i.e. tar, candle wax, glass)
Amorphous Solids:
Candle Wax
Particles of a solid
• Do not move fast
enough to overcome
the strong attraction
between them
• So they are held
tightly in place.
• The particles vibrate
in place.
Plasma
• Rare on earth. (lightning)
• Most common phase in the
universe
• Stars, like our Sun
• Matter in plasma phase is high in
energy, and is dangerous to living
things
Plasma
Plasma
Energy
• Ability to change or move matter
Phase Changes
• Melting
• Freezing
• Vaporization
• Condensation
• Sublimation
Phase Changes are
Physical Changes
Melting
• The change
from solid to
liquid
Freezing
• Liquid To Solid
• When a liquid
loses heat
energy
Liquid to Gas
• Vaporization
 change from a
liquid to a gas
• Evaporation
 Vaporization at the
surface of a liquid
Boiling
• Process by
which particles
inside the
liquid travel
into the air.
Condensation
• The change of
a substance
from a gas or
vapor to a
liquid
Sublimation
• To change phase (from a solid
or gas) without becoming a
liquid
Vaporization
• To be converted from a liquid
into vapor/gas
Evaporation
• Vaporization that occurs at the
surface of a liquid
Changes of State Graph
For Water
Conservation of Mass
Law of Conservation of
Mass
• Mass cannot be created
or destroyed
Law of Conservation of
Energy
• Energy cannot be created
or destroyed
Matter
Properties of
Matter
Section 2.3
Chemical Properties
• describes the way a substance
reacts with others to change into
a different substance
Chemical Changes
Reactivity
• the ability of a
substance to
combine
chemically with
another
substance
Physical Properties
• characteristics that can be
observed or measured
• without changing the identity of
the object.
 Shape, color, odor, texture…
Melting Point
• Temperature at
which a solid
changes to a
liquid.
• Aluminum M.P. =
660 °C
0
• 0 C for water at
sea level
Freezing Point
• Temperature at
which a liquid
changes to a solid
• Water F.P. = 0 °C
at sea level
Boiling Point
• Temperature a liquid boils at.
• B.P. of a liquid is related to
pressure above it.
• Water BP = 100 °C
• Table Salt BP = 1413 °C
• Diamond BP = 4200 °C
General Properties of
Matter include
• Mass
• Weight
• Volume
• and density
Density
• Density is the mass per unit
volume
Density
• density = mass / volume
 Or DMV
• Units
 Mass – g
 Volume – cm3
 Density – g/ cm3
Problem
• If 96.5 grams of gold has a
volume of 5 cubic centimeters,
what is its density?
Solution
• Step 1 Write the formula d=m/v
• Step 2 Substitute given numbers
and units d = 96.5 g/ 5 cm3
• Step 3 Solve for unknown variable
d= 19.3 g / cm3
Practice Problems
• 1. If 96.5 grams of aluminum
3
cm ,
has a volume of 35
what
is the density of aluminum?
• 2. If the density of a diamond
is 3.5 g / cm3, what would the
mass be if the volume is 0.5
cm3?
Solution
• Step 1 d=m/v
.
• Step 2 rearrange d v= m
• Step 3 Substitute given numbers
3
.
g/cm
3
.5cm
and units 3.5
=m
• Step 4 Solve for unknown
variable m= 1.75 g
Buoyancy
• The force with which a more
dense fluid pushes a less
dense substance upward.
Archimedes’ Principle
• The buoyant force on an object is
equal to the weight of the fluid
displaced by the object.
• Therefore if an object increases
it’s density it will sink, and if
decreases it’s density it will float.
Density Lab
Does it Float?
Does it Float?
• The density of water is 1 gram
per milliliter, 1g/mL.
• If the object’s density is
greater than 1g/mL, then the
object will sink.
• If the object’s density is less
than 1g/mL then it will float.
Does it Float?
• In this activity you will measure
the mass and volume of several
objects to obtain their densities.
• density = mass / volume
• Volume of cube=length x width x
height
• Volume of cylinder=p r2 h
Remember
1 cubic centimeter
= 1 mL
Volume of Cylinder
• Volume = p r2 h
Volume of a Cube
• Volume= L x W x H
Lab Report Format
Descrip Mas Volu Densi Does
tion
s
me
ty
it
(g) (mL) (g/m float
L)
?
•What
Quiz
kind of
solid is in
the
picture?
Quiz
•What kind
of matter
phase is in
the picture?
Name the Phase
Name the Phase
Name the Phase
Name the Phase
Gas – Pressure, Temperature
and Volume
• Boyle’s Law – if volume is reduced,
pressure will increase. P1V1 = P2V2
or P1/P2 = V2/V1
• Charles’s Law – if temperature of a
gas changes but pressure is the
same, then volume of the gas
changes. T1V2=T2V1 or T1/T2=V1/V2
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