By Sally Anderson

It matters

What is matter?Matter is anything that takes up space and

can be experienced by one or more senses (seeing, hearing, feeling, smelling, tasting)

What is a “state”?The condition or form that matter hasAlso referred to as phase

SolidA state of matter that has a definite shape

and volume.The particles (atoms or molecules) are

packed closely together. The forces between particles are strong

enough so that the particles cannot move freely but can only vibrate.

Solids can only change their shape by force, as when broken or cut.

LiquidA state of matter that has no definite shape,

but has a definite volume – takes the shape of the container.

It can drip.When a solid is heated above its melting point,

it becomes liquid. The molecules have enough energy to move

around and the molecules are farther apart than a solid.

GasA state of matter with no definite shape or

volumeGenerally it can’t be seenIt takes the shape of its surroundingsAlso called a vaporMolecules are quick and far apart

Why properties are important to scientistsWe study the properties of matter to

discover:What is it made of?How does it form?Where does it come from?

Property or characteristicCharacteristics or

qualities; the way something is or behaves

Example: A property of hydrogen, (H), is that it is extremely light in weight.

Other characteristicsIts colorIts shapeIts sizeIts massIts densityIts weightIts molecular structureHow it combines with

other substances

AtomsThe smallest pieces of matter (can’t see them with eyes)The atom is the smallest thing in our bodyDifferent kinds of atoms are called elementsCenter is called the nucleusMade of 3 particles

Nucleus contains protons (+ charge) and neutrons (no charge)

Electrons travel fast around the nucleus

Element

Different kinds of atoms are called elements

A substance that cannot be easily broken into smaller parts

Oxygen is an element that we breathe. Pairs of oxygen atoms join together to form an oxygen molecule.

Periodic table of elementsA table, or grid, showing the periodic

system in which all known elements are ordered by their weights

http://www.chemicalelements.com/http://www.dayah.com/periodic/http://periodic.lanl.gov/default.htm

MoleculeForms when two or more atoms combineAtoms can be the same element (like oxygen) O2Most molecules have atoms of more than one

element CO2; H20Sometimes molecules combine to form a new

molecule (burn coal & carbon atoms in coal combine with oxygen in air to make carbon dioxide)

Physical changesMelting:

Add heat energy to solid, it melts and becomes liquid

Evaporation:Add heat energy to liquid, it evaporates and

becomes a gasFreezing:

Take away heat energy from liquid, it freezes and becomes solid

Condensation:Take away heat energy from gas, it condenses and

becomes liquidIn a physical change into another substance –

water is still water, even if frozen

MeltingTurn from a solid to a liquid by adding heat

energyExample: melting solid gold to turn into

molten gold. Liquid gold can be poured into a mold. Remove heat energy (freezing) and it cools returns to a solid.

Example: NASA engineers have to find a way to protect the shuttle’s aluminum from melting (heat-resistant tiles)

FreezingProcess of liquid changing to a solidReleases heat (take away heat energy)Example: NASA engineers use fuel that is

colder than ice and if ice forms, it would break off and damage the space shuttle (they installed heater)

Evaporate or evaporationThe process of changing a liquid into a gas

or vapor by adding heat energyExample: place a pot on the stove and

some of the liquid will eventually turn into a gas

Example: A puddle after a rain storm evaporates into the air by turning into a gas

Condense or CondensationTo take away heat energy to turn a gas into a

liquidOccurs when water vapor cools (lose heat

energy)Example: water vapor (a gas) can form

outside a cold glass of juice on the table)Example: Water vapor forms liquid dripping

on outside of glass or a car windowExample: On space shuttle, NASA uses liquid

fuels (oxygen and hydrogen) in liquid state by removing heat and they store them in tanks

MassHow much matter is in somethingCan measure the mass, length and

temperature of matter

volumeThe amount of space inside an objectIn a 3 dimentional cube, multiply the length

x width x heightLxWxH

DensityHow much matter something hasMust compare the densities of solids that

have equal volumeIf they have equal volume, the heaviest (or

greatest mass) will be denser

MixingMixing is another type of physical changeExample: (water and oil mix and then

separate) They are still water and oil

DissolvingAnother type of physical changeWhen you dissolve something solid into

something liquid, you make a solutionExample: sugar and coffeeThe sugar is still sugar, even when mixed,

but it is harder to separate the sugar from the coffee than to separate the oil from the water

EnergyPowerExamples: heat energy, light energy, wind

energy, solar energy, nuclear energy,

Potential energyPossible or about to happenExample: The stacked cord of wood has

lots of potential energy because we can burn it to stay warm.

KineticMovement or motionExample: The horse race was filled with

kinetic energy as the horses moved around the track

ViscosityThe amount of friction within a liquidExample: Cold honey is very viscous

because it is hard to pour.If a fluid drips slowly, it is viscous.

Review solidsState

Definition Properties/ characteristics

Mixture change

Temperature and force changes

Solid Matter that can be touched and keeps its own shapeMade of atoms that are really close together

Keep their own shapeIf you add heat, they meltMade of atomsHave color; you can see themIf you apply force, it will breakMade of matter

Chemical reaction when they form together- can’t be separatedChemical change needed to separate it

Increase temperature will change solid to liquid (or gas)Increased pressure and force will change solids