Did you know that the Did you know that the average human nose can average human nose can recognize about 10,000 recognize about 10,000

different smells? different smells?

Pretty amazing, huh!?Pretty amazing, huh!?

Nature of MatterNature of Matter

What is Chemistry?? What is Chemistry??

hmmmhmmm

Describing MatterDescribing Matter

Properties of MatterProperties of Matter

What is Matter?What is Matter?

Matter – anything that has mass Matter – anything that has mass and takes up space.and takes up space.

(remember that the amount of space (remember that the amount of space something occupies is its volume)something occupies is its volume)

Some types of matter are substances Some types of matter are substances and some are not.and some are not.

Substance Substance

a single kind of matter that is a single kind of matter that is pure and a specific set of properties.pure and a specific set of properties.

(Pure = always has a specific (Pure = always has a specific makeup or composition)makeup or composition)

Describing MatterDescribing Matter

Physical PropertiesPhysical Properties

a property of matter that a property of matter that can be observed w/out changing the can be observed w/out changing the identity.identity.

ex. Color, odor, mass, volume, ex. Color, odor, mass, volume, state, and…..state, and…..

• Thermal Thermal conductivity – conductivity – ability to transfer ability to transfer thermal energythermal energy

• Malleability – can Malleability – can be pounded into be pounded into sheets (aluminum sheets (aluminum foil)foil)

• Ductility – can be Ductility – can be drawn or pulled into drawn or pulled into a wire.a wire.

• Solubility – can Solubility – can dissolve in another dissolve in another substancesubstance

• And Density – mass per unit And Density – mass per unit volumevolume

Formula D = m/vFormula D = m/v

Density of one substance is Density of one substance is usuallyusually different from another.different from another.

Most Dense Liquids have a higher Most Dense Liquids have a higher number and are located at the number and are located at the bottombottom

Good Egg vs Bad EggGood Egg vs Bad Egg

Density of Good Egg = 1.2 g/mlDensity of Good Egg = 1.2 g/ml

Density of Bad Egg = .9 g/mlDensity of Bad Egg = .9 g/ml

Density of water = 1.0 g/mlDensity of water = 1.0 g/ml

Result Result

Bad Egg FloatsBad Egg Floats

Physical vs Chemical Physical vs Chemical ChangesChanges

Physical ChangePhysical Change – – does notdoes not form a form a new substancenew substance

(most can be undone)(most can be undone)

Chemical ChangeChemical Change – does form a new – does form a new substancesubstance

CANNOT BE UNDONECANNOT BE UNDONE

Chemical changes often Chemical changes often involve:involve:

• Color changesColor changes

• Fizzing/foamingFizzing/foaming

• HeatHeat

• Sound/lightSound/light

• OdorOdor

Chemical PropertiesChemical Properties

One substances ability to change into One substances ability to change into a new substance w/ different a new substance w/ different properties.properties.

i.e. Wood burns and i.e. Wood burns and becomesbecomes

smoke & ashsmoke & ash

Chemical PropertiesChemical Properties

• Flammability – ability to burnFlammability – ability to burn

• Non-flammability – cannot burnNon-flammability – cannot burn

• Reactivity with - gasReactivity with - gas

acidacid

waterwater

ElementsElements

An element is a pure substance that cannot An element is a pure substance that cannot be broken down into any other substances.be broken down into any other substances.

!!!!Elements are the purest !!!!Elements are the purest substances!!!!substances!!!!

Elements composed of atoms.Elements composed of atoms.

AtomsAtoms combine to form molecules by combine to form molecules by creating chemical bonds.creating chemical bonds.

CompoundsCompounds – a pure substance made of – a pure substance made of two or more elements chemically two or more elements chemically combined in a set ratio. (different combined in a set ratio. (different properties than single elements)properties than single elements)

HH22OO

MixturesMixtures – made of two or more – made of two or more substances not chemically combined.substances not chemically combined.

HeterogeneousHeterogeneous - you can see the - you can see the different partsdifferent parts

HomogeneousHomogeneous – evenly mixed that you – evenly mixed that you cannot see the different parts.cannot see the different parts.

A solution is an example. A solution is an example.

Mixture SeparationMixture Separation

• MagnetMagnet

• FilteringFiltering

• DistillingDistilling

• EvaporationEvaporation

What is EnergyWhat is Energy

• EnergyEnergy is the ability to do work…. is the ability to do work….

– And that work causes an object to move And that work causes an object to move in the direction of the force.in the direction of the force.

– It is expressed in units called It is expressed in units called JoulesJoules (J) (J)

Forms of EnergyForms of Energy

1.1. ThermalThermal – is the – is the total K.E. of the total K.E. of the particles of an particles of an object (from hot object (from hot to cold) to cold)

2.2. Chemical Chemical – – energy required energy required to bond matter to bond matter particles together particles together (toasting (toasting marshmallows)marshmallows)

Thermal Imaging

Chemically bonded atoms

Endothermic vs Endothermic vs ExothermicExothermicEndothermicEndothermic – energy is absorbed – energy is absorbed

i.e. Melted cheese sandwich – the i.e. Melted cheese sandwich – the cheese takes in energy to melt.cheese takes in energy to melt.

The sun is also endo-The sun is also endo-thermic.thermic.

ExothermicExothermic – energy is released – energy is released

i.e. Welding of any kind releases i.e. Welding of any kind releases energy in form of sparks and heatenergy in form of sparks and heat

Endo vs Exo GraphsEndo vs Exo GraphsEndothermic Reaction

• Electromagnetic Electromagnetic energy-energy-

form of energy that form of energy that travels thru space as travels thru space as waves.waves.

• Electrical energy – Electrical energy – energy of electrically energy of electrically charged particles charged particles moving from one moving from one place to another.place to another.