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Chapter 2Matter and Change

Matter

uMatter is anything that has mass and takes up space.

Matter

u Mass is a measure of the amount of “stuff” (or material) the object contains (don’t confuse this with weight, a measure of gravity)

u Volume is a measure of the space occupied by the object

Describing Matter

u Properties used to describe matter.

u Properties are words that describe matter (adjectives).

u There are two type of properties:

u Physical Properties

u Chemical Properties

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Physical vs. Chemical Properties

u Physical Properties- a property that can be observed and measured without changing the material’s composition.

uExamples- color, hardness, m.p., b.p.

u Chemical Properties- a property that can only be observed by changing the composition of the material.

uExamples- ability to burn, decompose, ferment, react with, etc.

States of matter1) Solid- matter that can not flow (definite shape) and has definite

volume.

2) Liquid- definite volume but takes the shape of its container (flows).

3) Gas- a substance without definite volume or shape and can flow.

u Vapor- a substance that is currently a gas, but normally is a liquid or solid at room temperature. (Which is correct: “water gas”, or “water vapor”?)

States of Matter

Solid

Liquid

Gas

Definite Volume?

YES

YES

NO

Definite Shape?

YES

NO

NO

Result of a Temperature Increase?

Small Expansion

Small Expansion

Large Expansion

Will it Compress?

NO

NO

YES

4th state: Plasma - formed at high temperatures; ionized phase of matter as found in the sun

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Solid Liquid Gas

Melt Evaporate

CondenseFreeze

Add Heat Add Heat

Physical vs. Chemical Change

u Physical change will change the visible appearance, without changing the composition of the material.

uBoil, melt, cut, bend, split, crack

u Chemical change - a change where a new form of matter is formed.

uRust, burn, decompose, ferment

Quiz Timeu Identify each as physical or chemical change.

Melting Cutting banana Burning Candle

Carving Pumpkin Baking Bread Apple Rotting

Quiz Time

u Which of the following are physical changes.

u A. making caramel from sugar

u B. Carving a wooden figurine

u C. Freezing mercury

u D. Dissolving salt in water

u Classify each of the following as a substance or a mixture.

u A. silver

u B. alphabet soup

u C. Textbook

u D. Table salt (sodium chloride)