Classification of Matter

Composition of Matter

Properties of Matter

Matter and Chemistry

Chemistry

The study of the composition, properties,

and reactions of matter, particularly at the

level of atoms and molecules.

Matter-Anything with mass that takes up

space

Atom-Basic unit of matter

Compounds vs. Elements

Molecules- Two or more atoms joined

together.

Compounds- The combination of two or

more elements.

All compounds are molecules but not all

molecules are compounds.

Chemical Formula

-Shows how many elements or molecules

are in each unit of a substance

Example: H₂O = 2 hydrogen and 1 oxygen

Example: 2H₂O= 2 water molecules

Composition of Matter

• Substance: has a fixed

composition, either an

element or a compound

• Element: all atoms in

the substance have the

same identity

Classification of Matter

• Heterogeneous Mixture: combination of

substances in which different materials

can be easily distinguished

• Homogeneous Mixture: combination of

substances in which two or more gaseous,

liquid, or solid substances are blended

evenly throughout

Classify The Following as a

Substance or a Mixture:

• Copper Penny

• Salad Dressing

• T-Shirt (75% cotton, 25% polyester)

• Kool-Aid

• Milk

• Chalk (Calcium Carbonate)

Composition of Matter

• Solution: homogeneous mixture of particles so

small that they cannot be seen with a

microscope and will never settle to the bottom of

their container

• Colloids: heterogeneous mixture of particles

larger than those in solutions, but not heavy

enough to settle out

• Suspension: heterogeneous mixture containing

a liquid in which visible particles settle

Properties of Matter

• Physical Properties:

characteristics of a

material that can

change without

changing the identity

of its substances

• Examples: color,

shape, size, density,

melting point, boiling

point, flexibility

Properties of Matter

• Physical Changes:

changing only

physical properties

• changing size,

changing shape, or

changing state

Properties of Matter

• Chemical

Properties:

characteristics of a

substance that

indicate whether it

can undergo certain

chemical changes

• Examples:

flammability, reaction

to light

Properties of Matter

• Chemical Changes:

change of one substance to

another

• Rotting, burning, forming

bubbles or solids in a liquid,

rusting

Properties of Matter

• Conservation of

Mass: matter is never

created or destroyed

• Example: a log burns,

the matter left behind

or released is ash,

gases, and smoke.

The mass of all these

equals the mass of

the log

Chemical & Physical Changes

Which of the following undergo physical changes? Which undergo chemical changes?

1.Baking soda and vinegar produce CO2, H2O, and sodium acetate

2.A burning candle

3.Melting wax

4.Boiling water

5.An antacid dissolves in water and produces gases

6.Add mentos to soda

7.Add Kool-Aid powder to water