6th Grade Science Final

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What is the Scientific method?

Steps, Observation, Questions, Research, Hypothesis, Experiment, Conclusions, Report.

What is Physical Science?

physics and chemistry.

What does physics look at?

mechanics, electromagnetic, thermodynamics and kinetics.

What does chemistry look at?

organic, inorganic, electro-chemistry and analytical chemistry.

Speed

a measure of the distance an object travels per unit of time

Velocity

is the speed and the direction of a moving object

Acceleration

the measure of the change in velocity during a period of time

Gravity

attractive force that exists between all objects that have mass

Friction

force that resists the motion of two surfaces that are touching

Newton’s First Law

If the net force on an object is zero, the motion of the object does not change

Newton’s Second Law

Acceleration of an object is equal to the net force acting on the object divided by the objects mass

Newton’s Third Law

When one object exerts a force on a second object, the second object exerts an equal force in the opposite direction on the first object

Net Force

is the combination of all the forces acting on ab object

Inertia

tendency of an object to resist change in its motion

action force

force applied to an object

reaction force

force pushed back against the object

momentum

measure of how hard it is to stop a moving object

Work

**transfer of energy that occurs when a force is applied over a distance**

Power

rate at which work is done

Machines

any device that makes doing something easier

lever

made up of a bar that pivots about a fixed point (soda tab)

wheel and axel

axel attached to the center of a wheel and both rotate together

inclined plane

flat sloped surface (ramp)

wedge

incline plane with one or two sloping sides (door stop)

screw

inclined plane that is wrapped around a cylinder

pulley

\: grooved wheel with a rope wrapped around it -fixed : only changes the direction of the force -moveable : decrease the force needed to lift an object

Fluid

any substance that can flow and take the shape of the container that holds it

Pressure

amount of force per unit area applied to an object’s surface

Buoyant Force

upward force applied by a fluid on an object in the fluid

Pascal’s principle

states that when pressure is applied to a fluid in a closed container, the pressure increases by the same amount everywhere in the container

Bernoulli’s principle

when speed increases, pressure decreases

Energy

the ability to cause change

Kinetic energy

energy due to motion

Potential energy

energy due to the interactions between objects or particles (energy an object has due to its location)

Mechanical energy

total energy of an object or group of objects due to large scale motions, and interactions

Sound energy

energy that sound creates

Thermal energy

energy due to the motion of particles that make up an object (cooking food)

Electric energy

energy that an electric current carry

Light energy

also known as radiant energy= energy that electromagnetic waves carry (cell phones and microwaves)

Nuclear energy

energy that is stored in the nucleus of an atom

Non-renewable energy resources

energy resource that is available in limited amounts or that is used faster than it is replaced in nature

\-Fossil Fuels (coal, natural gas, and petroleum)

-Nuclear energy

Renewable energy resource

resource: energy resource that is replaced as fast as, or faster than, it is used

-Water (hydro-power)

- Solar energy (Sun)

\-Wind

Thermal energy

the sum of kinetic energy and the potential energy of the particles that make up a material

thermometer use

measures temp.

What does water freeze at in Fahrenheit?

32 degrees

What does water boil at in Fahrenheit?

212 degrees

What does water freeze at in Celsius?

0 degrees

What does water boil at in Celsius?

100 degrees

radiation

\-radiation: transfer of thermal energy from one material to another by electromagnetic waves (example=Sun)

conduction

transfer of thermal energy between materials by the collisions

convection

**transfer of thermal energy by the movement of particles from one part of a material to another**

Matter

anything that has mass and takes up spaces

atoms

small particles that are the building blocks of matter

nucleous

center of the atom

protons

positive (+)

neutrons

no charge, neutral (o)

electrons

surrounds the nucleus (electron cloud)

elements

substance with only 1 type of atom

compounds

type of substance containing atoms of two or more different elements chemically bonded together

chemical formula

shows the different atoms that make up a compound using their element symbols

Mixtures

matter that can vary in composition

heterogenous mixture

mixture in which the individual substances are not evenly mixed

homogemous mixture

mixture in which the individual substances are evenly mixed

Physical Properties

characteristic of matter that you can observe or measure without changing the identity of the matter

\-solid, liquid, gas (states of matter)

\-Mass

\-volume

\-melting point and boiling point

\-density

\-ability to conduct electricity (electrical conductivity)

Physical change

change in size, shape, form, or state of matter (example water being frozen into ice- liquid or solid it is still ice)

sublimation

solid changing directly to a gas

deposition

gas changing directly to a solid

Chemical change

a change of materials into another, new materials with different properties and one or more than one new substances are formed.

Reactants

**what are present before the reaction takes place and are on the left side of the equation**

Products

what are formed during the reaction and are on the right side of the equation

Boyle’s Law

Law: pressure of gas increases if the volume decreases and pressure of gas decreases if the volume increases.

Charles’ law

volume of gas increases with increasing temperature, if the pressure is constant (example: taking a balloon outside)

ion

an atom that is no longer neutral because it has gained or lost electrons

metals

\-all elements in group 1-12 are metals

- share some physical properties

\- shiny

\-ductility (pulled into thin wires)

-Malleability (hammered or rolled into sheets)

nonmetals

\- elements in-between the metals and nonmetals

-have properties of both metals and nonmetals

Valence electrons

the electrons in the outermost shell, or energy level, of an atom

Dot diagram

a model that represents valence electrons in an atom as dots around the elements chemical signal

Covalent bonds

a chemical bond formed when two atoms share one or more pairs of valence electrons (example= water)

Synthesis

two or more substances combine and form one compound

Decomposition

one compound breaks down and forms two or more substances

Replacement

an atom or group of atoms replaces part of a compound

Combustion

a substance combines with oxygen and releases energy

Endothermic reactions

reactions that absorb thermal energy and must have energy constantly added

Exothermic reactions

reactions that give off thermal energy

Catalyst

substance that increases the reaction rate by lowering the activation energy

Concentration

the amount of particles of solute in a given amount of solution (example salt in soup)

Solubility

maximum amount of solute that can dissolve in a given amount of solvent at a given temperature or pressure (example- sponge absorbing water)

Mechanical wave

waves that travel only through matter

wavelength

the distance from one point on a wave to the same point on the next

longitudinal wave

a wave vibrating in the direction of propagation.

transverse wave

a wave vibrating at right angles to the direction of its propagation.

frequency

the number of wavelengths that pass by a point each second Interactions

absorption

transfer of energy by a wave to the medium through which it travels

transmission

passage of light through an object

reflection

causes a wave to change direction

Sound waves

longitudinal waves that only travel through matter

outer ear

collects sound waves

middle ear

amplifies sound

inner ear

send signals to the brain

Electromagnetic Wave

wave that travels through empty space