Properties and

Changes of Matter

2.1 / 2.4 Notes

Properties of matter

� Extensive Properties –

� Property that depends on the amount of a

substance

� Volume, Mass, weight,

� Intensive Properties –

� Property that depends on the type and not the

amount of matter

� Density, Boiling point, melting point, malleability,

ductility, reactivity…

� Mass

� Volume

� Density

� Length

� Temperature

� Magnetism

� Ability to Conduct electricity

� State of Matter

Physical Properties

A quality or condition of a substance that can be observed or

measured without changing the substance’s composition.

� Strength / Hardness

� Flexibility

� Color

� Taste / Odor

� Freezing/Boiling /Melting Points

� Malleability

� Ductility

Physical Changes

� A change of matter from one form to another without a change in its chemical makeup.

�NO new substances are formed!

�ALL Phase changes are physical changes!

� Most physical changes are reversible –some are not!!!

Physical Change QuizYES or NO

� Dissolving Salt in Water

� Rusting of metal

� Making Kool-Aid

� Sharpening Pencil

� Playing with play-dough

� Melting Butter

� Burning Wood

� Freezing Water

� Crushing a can

� Breaking a glass

� YES

� YES

� YES

� YES

� YES

� YES

� YES

� YES

� YES

� YES

� NO

� NO

� NO

� NO

� NO

� NO

� NO

� NO

� NO

� NO

CHEMICAL Properties and Changes

Chemical Properties

� The ability of a substance to undergo a specific chemical change

Examples of Chemical Properties:•Reactivity - The ability of two or more substances to combine to form NEW substances.

•Flammability – Ability of a substance to burn

� Are Physical properties different

than Chemical?

� Yes!!!!!!!!!!

� Physical properties can be observed without changing the identity of the substance

� Chemical properties� not easily observed

� Describe which chemical change will or will not occur

Chemical Change

� A change that occurs when one or more substances change entirely into NEW substances.

� Chemical Reaction� Reactants � Products

� Law of Conservation of Mass (Matter):� Matter is not created nor destroyed

� mass of reactants = mass of products

� # of atoms of each element in the reactants = # of atoms of each element in the products.

Oxygen gas + Hydrogen Gas produces Water

O2 + 2H2 ���� 2H2O

Reactants ���� Products

2 Oxygen

4 Hydrogen

Law of Conservation of Matter

2 Oxygen

4 Hydrogen

�Conservation of MassO2 + 2H2 2H2O

If I start with 36 grams of reactant I will end with _____ grams of product?

36g = X

If the chemical reaction yields 72 grams of product I must have started with ____ of reactant.

X = 72g

If I have 128 grams of Oxygen and the reaction produces 144 grams of water then I must have started with _____ grams of Hydrogen.

128g + X = 144g X= 16g

�Signs of Chemical Changes

� Color Change

� Gas Produced – foaming/bubbles

� Precipitate Formed – solid formed

� Temperature Change

� Light produced

Physical vs Chemical

key words to look for:

Physical

� Evaporates

� Dissolves

� Freezes

� Melts

� Crush

� Shapes

� Breaks

� Bends

� Boils

Chemical

� Reacts with

� Burns

� Bakes

� Cooks

� Produces

� Decompose

� Ferment

� Corrode

� rots