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CRCT
Practice
S8P1.
Students
will examine the
scientific view of
the nature of
matter.
a. Distinguish
between atoms and
molecules.
– are the basic
building block of all matter.
Atoms
Each
kind of atom is an
element – a pure substance
that cannot be broken down
into simpler substances.
There
are 117 confirmed
elements. 90 of these
are found in nature and
the rest are synthetic
(man made)
Location Charge
Mass
Nucleus
+
1 amu
Neutron Nucleus
0
1 amu
Electron Electron
Cloud
-
Less
than 1
amu
Proton
Number – describes
the number of protons in
the nucleus of the atom.
Atomic
Mass – equal to the
number of protons plus the
number of neutrons in the
atom.
Atomic
Atom – occurs
when electrons equal
protons.
Neutral
A
molecule is the smallest
unit of a compound that
has all the properties of
the compound.
A
subscript is a small
number that tells you
the number of atoms of
each element in the
substance.
b. Describe the difference
between pure substances
(elements and
compounds) and
mixtures.
An
element is an pure
substance that cannot be
broken down into simpler
substances by ordinary
chemical means.
Compounds are pure
substances that are created
when atoms are chemically
combined.
Mixtures
form when two or
more substances combine
without joining together
chemically.
Heterogeneous mixtures –
look different throughout
Homogeneous mixtures –
look the same throughout
c. Describe the movement
of particles in solids,
liquids, gases, and
plasmas states.
A
state of matter is the
physical form in which
matter exists.
A
solid is a substance with
 definite shape and
volume
 Particles are densely
packed
 Energy binding the
particles is very strong
A
liquid is a substance that
 Has no definite shape
 Has definite volume
 Particles are less densely
packed and can flow around
each other
 Energy binding the particles
is strong
A
gas is a substance that has
 NO definite shape
 No definite volume
 The particle arrangement is
far apart
 The binding energy is very
weak.
Plasma
is a state of matter
that forms when
temperatures are high
enough to remove
electrons from their atoms.
d. Distinguish between
physical and chemical
properties of matter as
physical (i.e., density,
melting point, boiling point)
or chemical (i.e., reactivity,
combustibility).
Physical
Properties are
characteristics that can be
observed or measured
without changing the identity.
Chemical
Properties are
characteristics that
describes how a substance
will interact with other
substances during a
chemical reaction.
e.
Distinguish between
changes in matter as
physical (i.e., physical
change) or chemical
(development of a gas,
formation of precipitate,
and change in color).
Change – alters the
physical properties of a
substance without changing
the identity of the substance.
Physical
Change – occurs
when a substance is changed
into a new substance with
different properties.
Chemical
f.
Recognize that there are
more than 100 elements
and some have similar
properties as shown on the
Periodic Table of
Elements.
The
periodic table is a
chart that organizes the
information about all of the
known elements according
to their properties.
– Horizontal Rows (7)
Groups – Vertical Columns
(18)
Periods
Elements
in the same
group have similar
properties.
These properties are a
result of their identical
valence electron numbers.
– describes how
likely an element is to form
bonds with other elements.
Reactivity
Most chemically active are
group 1 elements. (Due to
their 1 valence electron)
 Group 18 (Noble Gases)
are inert. This means they
cannot not form bonds with
other elements because
they are chemically stable.

Elements
on the left are
metals (except H)
Elements on the right are
nonmetals
Elements along the stair
step line are metalloids
g.
Identify and
demonstrate the Law of
Conservation of Matter.
The
law of conservation of
matter states that during a
chemical reaction, matter
cannot be created or
destroyed.
Mass of the reactant
equals the mass of the
product
A
coefficient is a number
that can show how many
molecules of a compound
are present.
S8P2. Students will
be familiar with the
forms and
transformations of
energy.
a. Explain energy
transformation in terms of the
Law of Conservation of
Energy.
Law of Conservation of
Energy – Energy is not
created or destroyed but can
be transferred.
Examples
of Energy
Transformations:
 Plants convert
electromagnetic energy from
the sun into chemical energy
through photosynthesis

Eating vegetables allows
your body to convert
stored chemical energy
into thermal energy to
maintain body temp and
mechanical to allow you to
move

The sun converts nuclear
energy into
electromagnetic and
thermal energy
b. Explain the
relationship between
potential and kinetic
energy.
Kinetic energy – the energy
of “motion”
Depends on mass and
velocity
Greater the mass; Greater the
KE
Greater the velocity; Greater
the KE
Potential energy – stored
energy
Ex.
Chemical Potential – energy
stored in chemical bonds
Elastic Potential – energy
stored in stretched or
spring objects
Gravitational Potential –
energy stored in objects
above Earth’s surface
c. Compare and contrast the
different forms of energy
(heat, light, electricity,
mechanical motion, sound)
and their characteristics.
Each
form of energy has its
own characteristics.
 Mechanical – Associated
with energy of motion
(kinetic).
 Thermal Energy – total
amount of energy in all the
particles


Heat – thermal energy
that’s transferred from
high to low temperature
Chemical Energy –
energy stored in chemical
bonds
Electrical Energy – energy
that results from moving
charges
 Electromagnetic – energy
resulting from the motion of
atoms

•Light, X-rays, Microwaves,
UV


Sound Energy – energy
given off by a vibrating object
Nuclear Energy – energy
stored in the nucleus of an
atom
•Released through Fission
and Fusion
d. Describe how heat can be
transferred through matter
by the collisions of atoms
(conduction) or through
space (radiation). In a
liquid or gas, currents will
facilitate the transfer of
heat (convection).
Temperature
is the measure
of the average kinetic energy
of particles.
Heat
is the transfer of
thermal energy between
objects at different
temperatures
 Flows from higher
temperature to lower
temperature
Heat
can be transferred
through matter in all three
phases and can be
transferred through a
vacuum (empty space).
Conduction – Heat is
transferred through solids
and liquids by direct contact
of the particles.
 Convection – Heat is
transferred through fluids
(liquids and gases) by
currents.


Radiation – transfer of
heat without matter –
uses electromagnetic
waves.
S8P3. Students will
investigate relationship
between force, mass, and
the motion of objects.
a. Determine the
relationship between
velocity and acceleration.
– a push or a pull
sometimes resulting in motion.
Force
Point – a generally
stationary point such as a
tree, or street sign that allows
you to define the motion of an
object in terms of speed,
position, and direction.
Reference
Speed
– how fast the object
moves.
Speed = distance / time
Units – m/s
Distance/Time Graph:
 Distance on the Y-axis
 Time on the X-axis
– speed of
the object in a given
direction.
Velocity changes
when the speed or the
direction of an object
changes.
Velocity
– the rate at
which velocity changes.
Acceleration changes if the
speed or its direction changes.
Formula:
 a = vf – vi
t
Units – m/s/s
Acceleration
b. Demonstrate the
effect of balanced and
unbalanced forces on
an object in terms of
gravity, inertia, and
friction.
Force – the sum
of the forces acting on
an object.
Net
Forces –
equal forces acting in
opposite direction
Net force equals zero
Balanced
Unbalanced
Forces
 Net force is greater than
zero
 Object moves in the
direction of the greater
force
 Can cause a change in
the motion of an object
– an object’s
resistance to a change
in motion.
 Greater Mass –
Greater Inertia
Inertia
– the force that
opposes the motion of an
object
Friction
Static – no motion
 Sliding – objects sliding
past each other

Rolling – objects rolling
past each other
 Fluid – friction from a
liquid or gas

– force of attraction
between all objects.
 Depends on Mass and
Distance
Gravity
c. Demonstrate the
effect of simple
machines (lever,
inclined plane, pulley,
wedge, screw, and
wheel and axle) on
work.
– when a force is applied
to an object and the object
moves in the direction of the
force.
W = F x d
 Only occurs when the object
moves in the direction of the
force
Work
Machines
– makes work
easier by:
Multiplying effort force
Changing direction of
force
Increasing Distance
6
Simple Machine
 Levers
 Pulleys
 Wheel and Axle
 Inclined Plane
 Wedges
 Screws
– a bar that is free to
pivot about a fixed point
 Force Applied – Effort
Force
 Resistance – Load
Lever
3 classes of Levers
– a rope or chain
wrapped around a wheel
 Makes work easier by
changing direction of the
force
 Block and Tackle pulleys
multiply effort force
Pulley
and Axle – consists
of two wheels of different
sizes.
 Larger – Wheel
 Smaller – Axle
 Makes work easier by
increasing the effort force
Wheel
Plane – a
straight, slanted surface
Makes work easier
allowing you to use
less effort over a
greater distance
Incline
– an inclined
plane that is wider or
thicker at one end than
the other
 Makes work easier by
changing the direction of
the effort force
Wedges
– an inclined
plane that is wrapped
around a cylinder
Makes work easier by
increasing the number
the threads
Screw
S8P4. Students will
explore the wave
nature of sound and
electromagnetic
radiation.
a. Identify the
characteristics of
electromagnetic and
mechanical waves.
– any disturbance
that transfers energy
through matter or space.
Wave
– the material
through which waves can
travel
Medium
Mechanical
Wave - a wave
that needs a medium
Transverse Wave – a wave
that transfers energy in a
direction that is perpendicular
to its medium.
Longitudinal Wave –particles
move back and forth.
Electromagnetic
Wave
– A wave that doesn’t
need a medium through
which to travel
b. Describe how the
behavior of light waves
is manipulated causing
reflection, refraction
diffraction, and
absorption.
When
a wave hits an
obstacle, passes from
one medium to another,
or hits another wave, it
is possible that it will
change speed, direction,
or shape.
– occurs when
a wave bounces back after
striking a barrier.
 Sound Reflection = Echo
 Light Reflection in mirror
allows you to see yourself
Reflection
Refraction
- the bending of a
wave as it passes at an angle
from one medium to another.
 Light Refracts (bends)
•Enters a lens
•Enters a prism
•Enters water from air (bent
pencil)
– refers to the
bending, spreading, and
interference of waves when
thy go through a narrow
opening.
 When waves pass through a
slit, a pattern of ripples forms
in all directions
Diffraction
Interference
– when two
waves collide
 Constructive – crest hits
crest
 Destructive – trough
hits trough
– passing
of waves through a
medium
 Transparent– most of
light transmits through
the material
•Windows, Plastic Wrap
Transmission
Absorption
disappearance of an EM
wave into a medium
 Opposite of Reflection

You see different colors
due to reflection and
absorption
•An apple looks red b/c
all colors but red are
absorbed and red is
reflected back to your
eye
c. Explain how the
human eye sees
objects and colors in
terms of wavelengths.
Your
ability to see
involves the reflection
of light.
The
Eye
 Cornea – transparent
material helps move light into
the eye
 Pupil – small hole that
adjusts size in order to
control amount of light
entering
Lens – responsible for
focusing light
 Retina – where the light rays
focus the image
 Optic Nerve – relays
information about image to
brain

Spectrum –
collection of all EM frequencies
 Radio waves – longest
wavelength, lowest frequency
•Used in AM & FM
broadcasting
Electromagnetic
Microwaves – More energy
than radio waves.
•Radar
 Infrared Light – associated
with heat.


Visible Light – only part of
spectrum that you can see
•Longest Wavelength is Red
•Shortest Wavelength is
Violet
•You see color because of
the way light interacts with
an object.

Ultraviolet Light – have a
higher frequency than
visible light
•Can cause reactions: tan
the skin, too much may
lead to skin cancer
X-rays – can travel through
soft tissue, such as skin, but
not through hard bone.
 Gamma Rays – have the
shortest waves and highest
frequencies
•Most Energy on Spectrum

d. Describe how the
behavior of waves is
affected by medium
(such as air, water,
solids).
In
order to see any object, it
must give off light.

Luminous – objects that
emit their own light

Illuminated – objects that
reflect light to your eyes
•Amount of reflected light
depends on the surface.
(Smooth reflects more
light than rough
surfaces.)
of Reflection – the
angle at which any wave
strikes a reflecting
surface is equal to the
angle at which the wave
is reflected
Law
– material that
permits light to pass through
Translucent – material
transmits some light
Opaque – allow no light to
pass through
 (Wood, Carpet)
Transparent
e. Relate the
properties of sound
to everyday
experiences.
Sound
is a form of energy
produced by vibrating
objects.
 Mechanical Wave (needs
a medium)
 Longitudinal Wave
(moves back and forth)
– highness or
lowness of a sound
Frequency – number of
waves that pass a fixed
point in a given time
period
Pitch
Human
Ear
 Outer – collects sounds
 Middle – transfers energy
into inner ear by vibrating the
3 small bones
 Inner – cochlea stimulates
nerve cells and sends signal
to auditory nerve.
Effect – change in
the frequency of a sound
due to a moving sound
source or a moving listener
Resonance – ability of
objects to pick up the
frequency of a nearby
object
Doppler
f. Diagram the parts
of the wave and
explain how the parts
are affected by
changes in amplitude
and pitch.
– is a
measure of wave energy.
Height of the wave
Amplitude
– the distance
between two successive
points on a wave
 Crest to Crest
or
 Trough to Trough
 Compression to
Compression
 Rarefaction to Rarefaction
Wavelength
– the number
of waves produced in a
given amount of time
Higher Frequency =
Shorter Wavelength
Lower Frequency =
Longer Wavelength
Frequency
– refers to the highness
or lowness of a sound.
 Determined by the frequency
of the sound.
•Low Pitch = Low Frequency
•High Pitch = High
Frequency
Pitch
Speed – speed at
which a wave travels
Wave

Speed = wavelength x
frequency

Affected by :
•Medium through which
wave is traveling.
Mechanical Waves travel
fastest through solids
Electromagnetic Waves
travel at the same speed
S8P5. Students will
recognize
characteristics of
gravity, electricity,
and magnetism as
major kinds of forces
acting in nature.
a. Recognize that every
object exerts gravitational
force on every other object
and that the force exerted
depends on how much
mass the objects have and
how far apart they are.
– an attractive
force that works to pull
objects together.
Law of Universal
Gravitation – the force
of gravity acts between
all objects in the universe
Gravity
Gravitational
Force depends
on:
 Mass – amount of matter
 Distance
 Greater the Mass; Greater
the gravitational attraction
 Closer Distance; Greater
gravitational force
Newton’s
st
1
Law of
Motion – an object in
motion stays in motion,
an object at rest stays at
rest unless an
unbalanced forces act on
it.
– tendency of
an object to resist a
change in its motion.
Greater Mass;
Greater Inertia
Inertia
The
moon is able to
continuously orbit
Earth because the
Moon’s inertia and
Earth’s gravity are
balanced.
b. Demonstrate the
advantages and
disadvantages of series
and parallel circuits and
how they transfer
energy.
Electrical
Energy is
produced by the
movement and
distribution of charged
particles from the
atom.
Current –
the flow of electric
charges.
Unit – Ampere (A)
Electric
Potential
Difference
(aka Voltage) – results
from the differences in
electrical charges in two
locations.
Unit = Volts (V)
– a path through
which electricity can flow.
Energy Source – “push”
charges through circuit
(battery – greater
voltage; greater “push”)
Circuits


Load – operates using
electrical energy (“light
bulbs”)
Conductors (Wire) –
material that allows electrical
energy to flow easily
Circuit – a circuit
that provides one
possible path for the e- to
flow
One bulb burn out – all
bulbs burn out
Series

All loads share the
same energy source
•More bulbs added;
dimmer lights get
Circuit – offers more
than one path for the flow of
electricity.
 Each load has its own closed
pathway
 If one bulb burns out; the
others are unaffected
 Loads do not share a current.
Parallel
c. Investigate and
explain that electric
currents and magnets
can exert force on
each other.
Force – a push or a
pull that is exerted by a
magnet
 Magnets have 2 poles –
north and a south pole
 Cutting a magnet in half
gives you two smaller
magnets with a N & S pole.
Magnetic
Field – area
surrounding a magnet in
which the magnetic force
exists
Lines extend from one
pole of the magnet to
the other
Magnetic
–
production of a magnetic
field by an electric current
 Electric current flows
through a coil of wire a
magnetic field is produced
similar to a bar magnet.
Electromagnetism
–
magnet that is made by
passing an electric
current through a coil of
wire wrapped around an
iron core.
Electromagnet
Usefulness
of electromagnets:
 Temporary – they can be
turned off and on
 Strength of magnet can be
increased
•Increase strength of current
•Add more coils
•Increase size of core
Motor –
transforms electrical
energy into mechanical
Generator – transforms
mechanical energy into
electrical
Electric