Science Final Review Notes

First, We Need To Know Length!!

Length: the unit of measure to determine the distance of an object

Mass• Mass: the amount of matter in a given

object

We use a BALANCE to measure mass

I can’t hear it…turn it up!!! Turn what up????

• VOLUME: the amount of space an object takes up

1. You can use the mathematical equation:

volume of cube= length x width x height

2. Use a graduated cylinder

3. See how much water it displaces by placing it in water

When You Combine Mass and Volume, you get…

• Density

A measure of the amount of matter that occupies a given amount of space

Amount of Matter

SPACE

Does it Float or Sink?

Density is less than 1.0 g/cm3

Density is more than 1.0 g/cm3

FLOATS

SINKS

Observation – Any use of the senses to gather information.

Inference – An conclusion drawn from a small sampling of data.

Solids

• Phase of matter in which matter has a definite shape and volume

Molecules (small round objects)

are arranged and organized in

“tightly packed” order

Liquids

• Phase of matter in which matter takes the shape of its container and has

definite volume

Molecules are moving slowly; not fast enough to overcome the

attractions between them

Gases

• Phase in which matter changes in both volume and shape

Molecules move very quickly and are able to break apart from one

another

So How Do We Classify Them?

• How fast the molecules move!!!

Solids Liquids Gases Plasmas

Molecules move slow and vibrate

in place

Move faster than solids and overcome

some attraction

Move fast and

overcome all of

attraction

Move incredibly fast but

break apart

• The seven types of energy are:

Energy

Heat

Light

ElectricalMechanic

al

Sound

Nuclear

Chemical

What Makes An Object Move?• Force: a push or pull on an object

Characteristics of Forces

1. Have size

2. Direction

40.0 Newtons

3. Units = Newtons

What is Friction Then?o Friction: a force that

opposes motion between two surfaces that are touching

There is NO SUCH THING as a

completely smooth surface!!

Newton’s Laws

1. An object in motion tends to stay in motion unless acted upon by an outside force

2. Force = mass x acceleration

3. For every action, there is an equal and opposite reaction

Levers

• A simple machine consisting of a bar that pivots at a fixed point

Fulcrum: pivot point

Inclined Planes

• Simple machine that is a straight, slanted surface

The longer an inclined plane is compared to its height, the greater the mechanical

advantage

Wheel and Axle

• Consists of two circular objects of different sizes

The wheel allows the individual to spin the axle easier

1st Circular Object

2nd Circular Object

Pulleys

• Consists of a grooved wheel that holds a rope or a cable

Compound Machines

• Machines that are made of two or more simple machines

The more moving parts, the more mechanical advantage

Efficiency In Machine

• Machines can be made to be more efficient

We do this by REDUCING…

Lubricants: substances that are applied to surfaces to reduce friction between them

Law of Conservation of Energy

• Energy cannot be created or destroyed. Energy can only change form.

• Potential Energy – Stored energy

• Kinetic Energy – Energy of motion

• The motion of molecules increases when heated and decreases when cooled.

• When energy is transformed from one form to another heat is the type of energy that is almost always a byproduct.

What happens to substances when they are heated or cooled?• When objects are heated...they

• When objects are cooled...they

***Water is the only exception...it actually expands as it cools

Conductors

• Materials that negative charges move easily through

• Charges are free to move around

Good conductors: metals such as silver, aluminum, copper, and mercury

Insulators

• A material in which negative charges do not move well

Found on electrical wire to keep you from shocks

Good Insulators: Plastic, rubber, glass, wood, and air

What Is A Current?

• Current: the rate at which charges pass a given point

Made by electrons moving in a wire

Circuits

• Complete, closed path through which electric charges flow

Closed Open

Two Types of Circuits

• 1. Series: all parts are connected in one loop

Types Of Circuits

• 2. Parallel: different loads are located on separate branches

Magnetic Poles• Every magnet has two poles

The parts of a magnet where the magnetic effects are the greatest

Types Of Waves

• 2 Types

1. Transverse Waves

2. Longitudinal Waves

These two waves can be identified by the direction in which the particles of the

medium vibrate compared with the direction in which the waves travel

Transverse Waves

• Transverse: waves that move across

Particles in a transverse wave move across or perpendicular to the direction of the wave

Longitudinal Waves• Longitudinal: the particles of a medium

vibrate back and forth along the path that the wave travels

Properties of Waves

• Amplitude: the maximum distance the wave vibrates from its rest position

Larger the amplitude = taller wave

What Does Amplitude Mean?

• Small Amplitude = low energy

• Large Amplitude = high energy

Wavelength• Wavelength: the distance between

any two adjacent crests or compressions

Frequency

• Frequency: the number of waves produced in a given amount of time

Expressed in Hertz

Sound Waves are Longitudinal

Remember COMPRESSIONS and RAREFACTIONS!!!!

SOURCE

Rarefactions

Compressions

What Is Light?

Electromagnetic Wave (EM): a wave that travels through matter or space and consists of electric and magnetic fields

Field: area around an object that can exert a force, push, or pull on another object

No contact is needed

Refraction Bending of a wave as it passes at an

angle from one medium to another

Reflection

Allows us to see objects that do not produce their own light

When light or any other waves bounces off an object

Light and Color Color is produced by REFLECTION

and ABSORPTION!!!!

The colors that are REFLECTED are the colors that you can see!!!!!!

What Are Our Basic Colors?

THE RAINBOW!!!Meet ROY G. BIV

ROYGBIV

= RED= ORANGE= YELLOW= GREEN= BLUE= INDIGO= VIOLET

Electromagnetic Spectrum

• Name for the range of electromagnetic waves when they are placed in order of

increasing frequency

Electromagnetic Spectrum Continued

long Wavelength short

low Frequency high

Mixtures vs. SolutionsMatter that consists of two or more substances mixed together but not chemically combined

Type of chemical mixture formed when one substance is dissolved in another

Example: Water and Oil

Water will be found on the bottom separated from the oil

Example: Sugar and Water

The sugar “disappears” in the water

Example: Chocolate Syrup and Milk

The syrup will fall to the bottom after letting it settle

Example: Chocolate powder and Milk

The powder will “disappear” in the milk

Solubility

The amount of solute that can be completely dissolved in a given amount of solvent at a specific temperature

SOLUBLE INSOLUBLE

Substance that is able to DISSOLVE in another

Substance is not able to dissolve in another

Solute – The part that gets dissolved

Solvent – The part that does the dissolving

ElementsA pure substance that cannot be broken

down into other substances

Water

Hydrogen Oxygen

Gold

Gold

Molecule – Are composed of atoms of two or more elements.

The Atom3 parts

1. Protons = positive charge

2. Neutrons = neutral charge

3. Electrons = negative charge

Protons +

Neutrons

=Nucleus

Change of State Diagram

Physical Properties

Can be observed without changing what the object originally was

EXAMPLES OF PHYSICAL PROPERTIES

Hair

Chalk

Apple

Water

Color Shape ColorTaste

Color Texture Liquid Clear

Physical Changes

Changes in size, shape, or color (the object is still the same substance)

EXAMPLES OF PHYSICAL CHANGES

Hair

Chalk

Apple

Water

HAIRCUT STILL HAIR! SLICEDSTILL AN APPLE!

BREAK STILL CHALK!COLORING

STILL WATER!

Chemical Changes

Evident when we make a NEW SUBSTANCE!!

EVIDENCE OF PHYSICAL/CHEMICAL CHANGES

PHYSICAL CHANGES CHEMCIAL CHANGES

Size Bubbling

Shape Flammable

Color Dissolving/Dissolves

Solubility Curves

** A WAY TO FIGURE OUT HOW MUCH

SUBSTANCEYOU CAN DISSOLVE AT

DIFFERENT TEMPERATURES**** Match the

temperature at the bottom with the grams

of solute on the left side…where they meet is the solubility for that

substance**