Transcript File

THE MATERIAL WORLD
THE ORGANIZATION OF MATTER
PROPERTIES OF MATTER
FORMS OF ENERGY
FLUIDS
WAVES
THE ORGANIZATION OF
MATTER
KEY WORDS:
• Matter
• Pure Substance
• Pure Elements
• Pure Compounds
• Atom and Molecule
• Chemical Bond
• Mixtures: Homogenous & Heterogeneous Mixtures
• Solution: Solute & Solvent
• Particle Model
• Phases of Matter: Solid, Liquid Gas
• Behavior of Matter
MATTER
The air we breathe, the water we consume and
the materials we use are all made up of matter.
MATTER is anything that has volume or mass.
• An ATOM is the smallest unit forming matter
• A MOLECULE is a group of atoms attached by
chemical bonds
Example: A water molecule is formed by 2 hydrogen
atoms bonding to one oxygen atom
PURE SUBSTANCES
When all the particles in a substance are identical,
we consider it a pure substance.
There are two types of Pure Substances:
1. Pure Elements: Made up of only ONE type of
atom. Gold (Au) is made of Au atoms only.
2. Pure Compounds: Formed by TWO or MORE
different atoms combining. Water (H2O) is made
up of two different atoms (2 hydrogen atoms
and 1 oxygen atom)
These 3 atoms have chemically bonded to
create the molecule H2O (water).
MIXTURES
Atoms and molecules can be mixed together
without forming chemical bonds: this is called a
mixture or solution.
There are two types of Mixtures:
1. Homogenous: Made up of at least 2 substances
that cannot be distinguished individually by the
naked eye.
2. Heterogeneous: Made up of at least 2
substances that can be distinguished individually
by the naked eye.
SOLUTIONS & SOLUBILITY
Solution: A solution is a homogenous mixture in which it
is impossible to distinguish its constituents (what it is
made of). A solution is usually transparent.
Solute: A substance that dissolves in another substance.
Solvent: A substance that can dissolve a solute.
Solubility: the amount of solute that can be dissolved in a
given solvent. Water is typically the universal solvent.
Colloid: A homogenous mixture in which at least 2
different substances can be seen under a magnifying
instrument.
Example: Blood is a colloid, under a microscope we can
see both red and white blood cells. Milk is also a colloid.
HOMOGENOUS VS. HETEROGENEOUS
MIXTURES
HOMOGENOUS MIXTURE
• Composed of at least 2 pure
substances
• Particles are uniformly
distributed
• 1 or more substances
(SOLUTES) are dissolved in a
larger quantity of another
substance (SOLVENT)
• Contain 1 phase
• Also called solutions
• EX: Water and Salt
HETEROGENEOUS MIXTURE
• Composed of at least 2 pure
substances
• Particles are not uniformly
distributed
• Substances are not soluble
in a solvent
• Contain 2 or more phases,
which can be seen by the
naked eye
• EX: Water and Sand
PARTICLE MODEL
• A model is a visible representation of a situation
that is abstract, hard to access or completely
hidden.
• Particles are naturally attracted to each other
• The closer particles are to each other, the stronger the
forces are.
• Particles are in constant motion
• Particles with a higher temperature move faster,
on average, than particles with a lower
temperature
• The higher the temperature of a substance, the more energy
its particles have.
PARTICLE MODEL (SOLIDS)
• Particles of SOLIDS are
very close together and
therefore strongly
attached to each other
• The result is a very
orderly arrangement of
particles
• Particles in a solid
substance vibrate but
do not actually move
around
PARTICLE MODEL (LIQUIDS)
• Particles in LIQUIDS are
somewhat close
together and therefore
somewhat attached.
• The arrangement of
molecules is NOT very
orderly
• Particles in a liquid
substance move around
each other very slowly
PARTICLE MODEL (GASES)
• Particles in GASES are
widely spread out and
weakly attached
• The particles are
arranged in a very
disorderly fashion
• Particles in a gaseous
substance move rapidly
in all directions
PROPERTIES OF MATTER
KEY WORDS:
• Physical Properties
• Chemical Properties
• Characteristic & Non Characteristic Properties
• Density
• Mass
• Volume
• Solubility
• Concentration
• Dilution
• Ratio
PROPERTIES OF MATTER
• A Property is information used to describe a
substance.
There are two types of Properties:
1.PHYSICAL PROPERTIES are those we can observe or measure
without changing the nature of the substance.
Examples: Boiling Point, Melting Point, Density and Solubility
2. CHEMICAL PROPERTIES describe how two properties react
with each other, therefore you must modify the nature of the
substance.
Examples: Reaction to indicators (Litmus paper, fire alarm,
pregnancy test)
CHARACTERISTIC VS. NON
CHARACTERISTIC PROPERTIES
A Non-Characteristic Property cannot help us tell
one pure substance form another.
Example: Saying the window is transparent will not
help us understand what the glass is made of. It can
be several things; glass, plastic, etc…
A Characteristic Property helps us to identify
precisely a pure substance.
Example: Melting point and Density are examples
of characteristic properties. Plastic and glass are
examples of transparent solids. Their melting points
and density, however, are very different.
DENSITY
DENSITY: Measures the amount of matter in a given
space. Every substance has its own specific density.
(Ratio of Mass/Volume)
• Example: The density of vegetable oil
(0.92g/ml)is less than water (1.0 g/ml) and
they cannot be mixed together; the oil
simply floats on the surface of the water.
• Example: The density of helium (gas) is
lower than that of air, which explains why
balloons filled with helium gas fly away.
CALCULATING DENSITY
M
Formula: p= M/V
p V
Mass is represented as g(grams)
Volume is represented as ml (liquid) cm3 (solid)
Example 1: A student measures the mass of an 8 cm3 block
of brown sugar to be 12.9g. What is the density of the brown
sugar?
p=M/V
12.9g (mass) / 8cm3 (volume) = 1.61g/cm3
Example 2: A chef fills a 50ml container with 43.5g of
cooking oil. What is the density of the oil?
p=M/V 43.5g (mass) / 50ml (volume) = 0.87g/ml
CALCULATING DENSITY
Example 3: Sam measures the mass of an empty cylinder to
be 32.5g. Then, he adds 40 ml of the unknown liquid. Finally, he
measures the mass of the cylinder with the liquid to be 82.9g.
Calculate the density of the liquid.
p=M/V 82.9g – 32.5g = 50.4g (mass of liquid)
p = 50.4g (mass) / 40ml (volume) = 1.26g/ml
Example 4: A piece of stone 12cm x 4cm x 4cm has a mass of
872g. What is the density of the stone?
p=M/V Volume= length x width x height (12 x 4 x 4 = 192cm3)
p = 872g (mass) / 192cm3 (volume) = 4.54g/cm3
SOLUBILITY
There is a limit to the amount of solute you can add to a
solvent. The maximum amount of solute in a solvent
corresponds to its solubility.
Unsaturated Solution: Contains less than the max
amount of solute.
Saturated Solution: Contains exactly the max amount of
solute. If it contains more than the max amount of solute,
a surplus solute will appear as a Precipitate.
Water Soluble: A substance that can be dissolved in
water.
Lipo - Soluble: A substance that can be dissolved in lipids
(fats).
CONCENTRATION
The concentration of a solution corresponds to the
quantity of dissolved solute in a given quantity of
solution (Gatorade powder in water).
Concentration increases when solute is added to
the solution.
A solutions concentration can be expressed in a
variety of ways:
• g/L (number of grams of solute per 1 liter of solution)
• % M/V ( number of grams (g) of solute per 100ml of solution)
• % V/V (number of milliliters (ml) of solute per 100ml of solution)
CALCULATING CONCENTRATION
C = Mass/Volume
• Solving for Concentration: Mass / Volume
• Solving for Mass: Concentration x Volume
• Solving for Volume: Mass/Concentration
Mass
Conc.
Volume
Mass = Solute (g) Volume = Total amount of Solution (L)
Concentration = Amount of dissolved solute in a given amount of
solution.
CONVERSION TABLE
kg x1000
Grams (g)
km
Meter (m)
kl
x1000
Liter (L)
÷1000
mg
mm
÷1000
ml
CALCULATING CONCENTRATION
Example 1: You are mixing 2500mg of powder in a 4000ml
solution. What is the concentration in g/L?
Steps for Example 1:
1. Convert g/L
3. Identify variables
2. Write down formula
4. Divide
Step by Step Answer:
1. 2500mg/1000 = 2.5g, 4000ml/1000 = 4 L
2. C= M/V
M
3. M= 2.5g V= 4L C= ?
C V
4. 2.5g / 4L = 0.625 g/L
C= 0.625 g/L
CALCULATING CONCENTRATION
Example 2: You have a mixture with a concentration of 12g/L
in a 50 ml solution. What is the mass in grams?
Steps for Example 2:
1. Convert g/L
3. Identify variables
2. Write down formula
4. Multiply
Step by Step Answer:
1. 50 ml/ 1000 = 0.05L, 12g/L (Conversion not necessary)
2. C = M/V
M
3. C= 12g/L V= 0.05L M= ?
C V
4. 12g/L x 0.05L = 0.6g
M= 0.6g
CALCULATING CONCENTRATION
Example 3: Converting %M/V ,%V/V and ml to g/L
A scientist is comparing the concentration of three different drinks. The
concentrations of the drinks are listed below. Which drink has the
lowest concentration?
CONCENTRATION OF DRINKS
Drink A: 0.65 g/ml Drink B: 12% M/V Drink C: 6.5g/100ml
Step by Step Answer:
Drink A: 1L = 1000ml, 0.65g x 1000ml = 650g/L
Drink B: 12% M/V = 12g/ 100ml, 100ml x 10 = 1000ml or 1L,
12g x 10 = 120g/L ****(Same procedure for %V/V, replace g for ml)
Drink C: 100ml x 10 = 100ml or 1L, 6.5g x10 = 65g/L
DILUTION
Dilution is a technique that involves decreasing
the concentration of a solution by adding
solvent.
********INSERT PIC FROM P.16*************
DILUTION
Formula:C1 V1=C2 V2
C= Concentration in g/L V = Volume in L or ml
C1: Original concentration of solution
V1: Original volume of solution
C2: New concentration of diluted solution
V2: New volume of diluted solution
** If concentration is represented as %M/V or %V/V, be
sure to convert all variables to g/L before solving.**
CALCULATING DILUTION
Example 1: You have a solution with a concentration of 60g/L.
You
add water to dilute the solution. The new concentration is 20 g/L in a
100ml solution. How much water in ml was added to the new
solution?
Steps for Examples 1, 2 & 3:
1. Write down formula
6. Isolate the unknown variable
2. Identify variables
7. Divide
3. Convert ml to L
8*. Convert L back to ml
4. Plug variables into formula 9*. Subtract V2-V1(to figure out
5. Multiply Brackets
amount of added water)
* Only use steps 8 & 9 when solving for V1*
**See Example 3 for extra steps (converting %M/V to g/L)**
CALCULATING DILUTION
Example 1:
Step by Step Answer:
1. C1 V1 = C2 V2
2. C1= 60g/L V1= ? C2= 20g/L V2= 100ml
3. 100ml / 1000 = 0.1L
4. (60g/L)(V1) = (20g/L)(0.1L)
5. 60 x V1 = 60V1 20 x 0.1 = 2
6.
60V1 = 2
7. 2 ÷ 60 = 0.033L
8. 0.033L x 1000 = 33ml
9. V2-V1
100ml – 33ml = 67ml
67ml of water was added to the new solution.
CALCULATING DILUTION
Example 2: OJ Delight juice has a concentration of 25g/L in a 300
ml solution. It was too concentrated. The company added 500ml of
water to the juice. What is the new concentration?
Step by Step Answer:
1. C1 V1 = C2 V2
2. C1= 25g/L V1= 300ml C2= ? V2= 800ml (300ml+500ml)
3. 300ml / 1000 = 0.3L
800ml / 1000 = 0.8L
4. (25g/L)(0.3L) = (C2)(0.8L)
5. 25 x 0.3 = 7.5 C2 x 0.8 = C2 0.8
6.
7.5 = C2 0.8
7. 7.5 ÷ 0.8 = 9.38g/L
The new concentration of OJ Delight is 9.38g/L
CALCULATING DILUTION
Example 3: A Scientist would like to dilute a 6.0% M/V
solution. He takes the original 400ml of solution and adds water
to prepare 2L of the new diluted solution. What is the
concentration of the new diluted solution in % M/V?
Extra steps for converting %M/V
 6.0% M/V = 6g / 100ml
 Convert ml to L 100ml x 10 = 1L (1000ml)
 Balance the ratio by also multiplying the 6g (6g x 10= 60g)
 Concentration expressed in g/L = 60g/L
 60g/L is the same concentration as 6% M/V and 6g/100ml
CALCULATING DILUTION
Example 3:
Step by Step Answer:
1. C1 V1 = C2 V2
2. C1= 6g/L
V1= 400ml C2= ?
3. 400ml / 1000 = 0.4L
4. (6g/L)(0.4L) = (C2)(2L)
5. 6 x 0.4 = 2.4
C2 x 2 = C2 2
6.
2.4 = C2 2
V2= 2L
7. 2.4 ÷ 2 = 1.2g/L
8. Convert back to %M/V( 1.2g/L ÷ 10 = 0.12g/100ml or 0.12%M/V)
9. The Concentration of the new diluted solution is 0.12 % M/V
FORMS OF ENERGY
Key Words:
• Energy
• Thermal Energy
• Radiant Energy
• Chemical Energy
• Mechanical Energy (Kinetic & Potential)
• Energy Transfer
• Energy Transformation
• Physical Changes
• Phase Changes (Sublimation, Deposition, Fusion, Freezing, Condensation, Vaporization)
• Dissolution
• Deformation
• Chemical Changes (Synthesis, Decomposition, Oxidation, Precipitation)
• Molecular Formula
ENERGY
Energy is the capacity to do work or produce change.
• When a person lifts his or her arm, we can see the arm
move. This movement involves work. It’s because of
energy that the work is produced.
• When the snow melts, it changes from a solid to a
liquid phase. This change is made possible because of
the energy from the sun.
• Energy is expressed in Joules (J). One J represents the
energy needed to lift an object weighing 1 N (Newton)
to a height of one meter.
• 1 N = 100g.
FORMS OF ENERGY
Thermal Energy is energy in the form of Heat
that comes from the random motion of particles
that make up a substance.
Examples of the work or change that can be accomplished by
Thermal Energy:
 The melting of snow by the heat of the sun’s rays
 The lifting of a hot air balloon by the burner’s heating of air
 The production of water vapor in order to advance the train
by the boiler of a steam engine
FORMS OF ENERGY
Radiant Energy is energy in the form of
Radiation that is contained in and transported
by electromagnetic waves.
Examples of the work or change that can be accomplished by
Radiant Energy:
 Producing images of the inside of the body using X – rays
 Getting suntanned and sunburned by ultraviolet rays
 Treating certain cancers with gamma rays (chemo therapy)
 Producing light from a light bulb to brighten a room
FORMS OF ENERGY
Chemical Energy is energy in reserve. On its own it doesn’t work
or create change. To get the energy, the chemical bonds need to
be reorganized. This means breaking the bonds to release energy
they contain, and remaking bonds differently. Thus changing the
molecular formula of the substance(s).
Examples of the work or change that can be accomplished by Chemical Energy:
 The operation of a car motor by the combustion of gasoline
 The burning of a candle to produce light
 Photosynthesis; energy from the sun being transformed and stored in
glucose molecules
 Cellular Respiration; helps living organisms use chemical energy stored in
glucose molecules to grow, move and think
FORMS OF ENERGY
Mechanical Energy is the energy that results from the
speed of an object, its mass and its relationship to its
surroundings.
Potential vs. Kinetic Energy: A person is standing and holding a rock
over a cliff. At this moment the rock has potential energy. As soon as the rock
is released from the grasp of the person the rock is using kinetic energy until it
hits the ground. If the rock is dropped from a higher position, mechanical
energy will increase (relationship to surroundings)
Speed vs. Mass:
Let’s use the example of a car to understand how
speed and mass can affect mechanical energy. If we compare the damage
caused by a car accident at 100km vs. 30km, we can see that the mechanical
energy of a car increases with speed. At the same speed, a large truck has
more mechanical energy than a car. Greater mass = greater energy.
FORMS OF ENERGY
Examples of the work or change that can be
accomplished by Mechanical Energy:
The creation of a crater by an asteroid
The spinning of windmill blades by the wind
The powering of a hydroelectric power
station by a waterfall
ENERGY TRANSFER vs.
TRANSFORMATION
Energy Transfer is the movement of energy from one place to
another.
Energy Transformation is the changing of energy from one form
to another.
*******INSERT PIC FROM PAGE 42**************
PHYSICAL vs. CHEMICAL CHANGES
Physical Changes are changes that do not affect the nature or
the characteristic properties of matter.
Examples of Physical Changes:
 Ice melting into liquid
 Adding salt to soup
 Folding a piece of paper
Chemical Changes are changes that do affect the nature or
characteristic properties of matter.
Examples of Chemical Changes:
 When baking soda and vinegar are mixed, we see gas being released
 When garbage decomposes in landfills, it breaks down into simpler atoms or
molecules
 The oxidation of iron (the formation of rust) releases energy
 Adding acidic substances to milk or cream produces a precipitate (curd), this is
how cheese is made
PHYSICAL CHANGES
There are 3 different types of Physical Changes
we will discuss:
1.Phase Change is the transformation from one state or phase to
another. There are 6 different phase changes:
(Sublimation & Deposition, Fusion & Freezing, Condensation & Vaporization)
2. Dissolution is the creation of a solution by a solute dissolving
in a solvent
3. Deformation means changing the shape of a material
PHASE CHANGE
******** INSERT PIC FROM PAGE 43******
DISSOLUTION
Solute and solvent particles gap in-between
each other. They do not have a chemical bond.
******Insert Pic From Page 47************
DEFORMATION
Some deformations are reversible (stretching a
coil spring) and some are permanent (tearing a
sheet of paper).
*******Insert Pic From Page 50*********
CHEMICAL CHANGES
There are 4 different types of Chemical Changes
we will discuss:
1. Synthesis is the formation of a complex molecule from atoms
or simpler molecules (H2O).
+
=
2. Decomposition is the transformation of complex molecules
into simpler molecules or into atoms (the opposite of Synthesis).
=
+
3. Oxidation is a chemical reaction involving oxygen or a
substance that has similar properties to oxygen.
4. Precipitation is the formation of a solid (precipitate) that is
less soluble, or not soluble, following the mixing of two solutions.
EXAMPLES OF CHEMICAL CHANGES
****** INSERT PICS OF SYNTHESIS p.54******
******DECOMPOSITION (GARBAGE)******
******* OXIDATION (RUST & BANANAS)*****
******PRECIPITATION(CHEESE CURDLING)*****
FLUIDS
Key Words:
• Liquid State
• Gaseous State
• Particle Model
• Forces of Attraction
• Compressible Fluid
• Incompressible Fluid
• Pressure
• Force
• Surface Area
• Volume
• Pressure Exerted
• Particle Collisions
• Depth & Density
WHAT IS A FLUID?
A Fluid is a substance that has the capacity to
flow and assume the form of the container into
which it has been poured.
 A liquid can be a fluid
 A gas can be a fluid
 A solid cannot be a fluid (Forms a pile instead of taking the
natural shape of a container)
******INSERT PIC FROM PAGE 67 (BOTTOM)********
Fluids Through the Particle Model
Particles in a liquid, such
as water, are:
 Somewhat close
together
 Held by relatively weak
forces of attraction
 Particles can slide over
each other to take on
the form of any
container
Particles of a gas, such as
air, are:
 Much farther apart
from each other
 Not bound together by
any forces of attraction
 They move in every
direction and occupy all
available space
Compressible vs. Incompressible
Fluids
Compressible Fluids
 A compressible fluid is one
that can be squeezed or
compressed.
 Its volume can change in
response to a change in
pressure.
 The volume of a
compressible fluid can
change because the space
between the particles in the
fluid can vary.
Incompressible Fluids
 An incompressible fluid is a
fluid whose volume cannot
be varied.
 Its volume cannot change
noticeably because the
particles in a liquid are
already very close together.
 The cannot be condensed
any more.
Compressible vs. Incompressible
Fluids
*****INSERT PICS FROM P. 68 & 69*********
PRESSURE
Pressure is the result of a force applied to a
surface.
If the force is great enough you can move or
even change the shape of an object.
In science, the concept of pressure involves both
force and the surface area on which that force is
exerted.
FORCE
Force is an action that modifies the movement of
an object (accelerate, slow down, change course) or
causes the object to change shape (shaping dough
when making bread).
Force can be produced by an action, but it can also
be produced by the attraction between the object
and the Earth. (a person standing on the ground is
subject to a force of attraction that depends on
his/her mass). The greater the mass, the stronger
the force.
SURFACE AREA
Surface Area is the exposed surface dimension
of an object that is exerting force onto another
object.
Example: The exact portion of a finger pressing down on a piano
key.
 The exact portion of a finger is the Surface Area.
 The action of a finger’s surface area pressing down on a piano
key is the Force.
***********INSERT PIC FROM PAGE 70******************
FORCE & PRESSURE
The effect of a variation in Force on Pressure, if
Surface Area remains constant;
 If the Force increases, Pressure increases
 If the Force decreases, Pressure decreases
 The stronger the force, the greater the pressure
Example: A person with more mass sinks deeper in a lot of snow
than a person with less mass because the person with more mass
exerts a greater pressure.
The mass of the person = Force
The Force that is applied to the snow = Pressure
SURFACE AREA & PRESSURE
The effect of a variation in exposed Surface
Area on Pressure, if Force remains constant;
 If the Surface Area exposed to a force increases, Pressure decreases
 If the Surface Area exposed to a force decreases, Pressure increases
 The greater the Surface Area that is exposed to the force, the less
Pressure there is exerted
Example: A person who is not wearing snowshoes sinks deeper
in the snow because the Surface area that is in contact with the
snow is smaller.
The person wearing snowshoes was able to distribute their
weight evenly onto a larger surface area, thus applying less
pressure.
PRESSURE EXERTED BY A
COMPRESSIBLE FLUID
The particles of a compressible fluid (gas) move randomly in all
directions. When they meet an obstacle (object, wall of a
container, another particle), they change direction. During each
collision, the fluid particles exert a force on the obstacle. It is the
sum of these forces that create the pressure of a compressible
fluid.
In a compressible fluid, the Pressure depends on:
 The number of collisions with other particles or objects.
The more collisions there are, the greater the pressure.
Factors that affect the number of Collisions:
 Number of Particles, the more particles, the more they collide.
 Temperature, the higher the Temp., the faster the particles.
 Size of container, the smaller the container, the less room for
particles to move around freely without colliding.
PRESSURE EXERTED BY A
COMPRESSIBLE FLUID
Examples of Pressure exerted by a Compressible Fluid in
everyday life.
*INSERT PIC OF SCUBA TANK GAUGE & TIRE PRESSURE GAUGE*
PRESSURE EXERTED BY AN
INCOMPRESSIBLE FLUID