CLASSIFYING MATTERSection 2.1

What is Matter?

Matter is…

…anything that takes up space (has volume) and has mass

Essentially… anything made of atoms

Properties

All matter has different properties because of different structures/compositions

Types of Matter

Pure Substances have a definite, fixed composition

Compositions of a Mixture can vary

Pure Substances Two kinds: element and

compound

Elements cannot be broken down into simpler substances

Smallest particle of an element is an atom

118 different elements = 118 different atoms

Pure Substances

Compounds are made up of two or more elements chemically bonded together

Elements have SYMBOLS!

Compounds have FORMULAS!

Pure Substances

The properties of a compounds ARE OFTEN DIFFERENT from the properties of the elements that make up that compound!

Mixtures

Composition of a mixture can vary

Example: In a mixture of A, B, and C… you could have a little more A and a little less C, or any other combination.

Types of Mixtures

Heterogeneous mixtures have obviously different parts

Homogeneous mixtures (aka. solutions) have multiple substances evenly distributed

Other Important Terms

Solution: particles are too small to be filtered or scatter light; will not separate into layers

Suspension: cloudy (scatter light); large particles will separate into layers over time

Other Important Terms

Colloid: mostly small particles, but some larger-sized ones

Colloids do not separate into layers

Colloids do scatter light

PHYSICAL PROPERTIESSection 2.2

Properties of Matter

Chemical Properties can only be observed as the matter is changing into a different substance

Physical Properties can be observed using touch, smell, sight, or measurement; substance does not need to be changed

Physical Properties

Viscosity – resistance to flow (increases at cold temperatures, decreases at warm temperatures

Conductivity – ability to transfer heat or electricity

Physical Properties

Malleability – ability to be hammered into wires or sheets

Hardness – which substances can scratch which other substances?

Physical Properties

Melting Point

Boiling Point

Density = mass / volume

Units for density: g/cm3

Separating Mixtures

You can separate most mixtures based on their physical properties

Filtration (based on size of particles)

Distillation (based on boiling points)

Separating Mixtures

Physical Changes Properties change,

but material remains the same

Tye-dye Slicing Mixing or dissolving

Changes in STATE are physical changes

CHEMICAL PROPERTIESSection 2.3

Chemical Properties

Flammability

Reactivity

Toxicity

Chemical Changes

Any change in which one chemical substance changes into another chemical substance

Evidence: Color change Gas produced Precipitate produced

“Precipitate”

A solid that forms when two liquids react and separates out of the liquids

STATES OF MATTERSection 3.1

States of Matter

Solid Liquid Gas

Different states refer to…

States of Matter

Different states refer to…

1. Whether shapes/volumes are fixed or variable

2. Arrangement of atoms

Solids

Definite shape Definite volume

Atoms are packed so tightly they cannot move, only vibrate

Liquids

Definite volume No definite shape

Atoms are packed tightly together, but can flow

Gases

No definite shape No definite volume

Atoms are spread far apart and move quickly and randomly

Changes in State…

…are physical changes.

…occur as molecules speed up or slow down because of changes in temperature.

Changes in State

Evaporation

Condensation

Melting

Freezing

Sublimation

Deposition

TEST PREPOctober 21, 2011

Are you ready for the test? Have you read all the textbook

sections thoroughly?

Are you ready for the test? Have you gone, little-by-little, back

through your notes each night?

Are you ready for the test? Have you used the notes on

SlideShare?

Are you ready for the test? Have you practiced with the problems

in the back of the chapter?

Are you ready for the test? Have you re-written some difficult

terms/definitions or made flash cards?

Are you ready for the test? Have you checked the correct answers

to your ClassMarker quiz?

Are you ready for the test? Did you understand how to correctly

measure and calculate density in the lab?

Scores 6-7 : very well prepared

5: getting close; average preparedness; still work to be done

3-4: TROUBLE! much more work to be done

0-2: WHAT THE HECK HAVE YOU BEEN DOING FOR TWO WEEKS???

Element, Compound, Homogeneous, or Heterogeneous? Carbon

Sucrose (C12H22O11) Sugar dissolved in water Air Steel A leaf A crayon (without the paper) Silver Pure water Shampoo

Physical or Chemical Property?

Flammability Viscosity Melting Point Density Reactivity Conductivity Boiling Point Hardness Malleability Toxicity

Physical or Chemical Change? When you shake a soda, it foams out the

top when opened. Wood is burned in a campfire for heat. Silver polish reacts with the dirt stuck to

your jewelry and removes it. Cook eggs and bacon for breakfast. A sample of gold is flattened into a sheet of

gold foil. Carbohydrates and proteins are broken

down by your cells for energy. Alcohol boils and is collected in a new

container.

Scores 24-27 : very well prepared

18-23: getting close; average preparedness; still work to be done

12-17: TROUBLE! much more work to be done

0-11: WHAT THE HECK HAVE YOU BEEN DOING FOR TWO WEEKS???