Matter (audio) r1

Structure of Matter
What is Matter?

Everything in the Universe can be classified as
either matter or energy! So what is matter?

Define matter: Matter is anything that has mass and occupies a
volume.
Matter is the “stuff” the Universe is made of

A Kaboom Key Concept!
1. All matter is composed of very tiny particles

This is the first statement of the Particle Model of Matter.
2. Particles are in constant motion.
3. Particles have spaces between them. The spaces are
much larger than the particles themselves.
4. Particles are attracted to each other by electrostatic
forces. 2

Particles are in constant motion . . .

The energy of the particles in matter determines particle motion and
affects the how far apart the particles are from each other.

We can think of particle energy as TEMPERATURE.

As temperature increases , the average energy of the
particles increases

The temperature determines

the phase or state of the matter

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Three Phases of Matter

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Adding heat allows particles to overcome the
attractive forces that pull them together.

Add heat
5

Solids – definite volume and shape; particles packed in
fixed positions; particles can vibrate back and forth only

6

Liquids – definite volume but indefinite shape; particles
close together but not in fixed positions; particles are
free to move (rotate)

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Gases – neither definite volume nor definite shape;
particles are at great distances from one another;
particles are free to move (translate)

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Plasma – a plasma is an ionized gas. Plasma shares
similar characteristics to gases.
A plasma is also a very good conductor of electricity and
is affected by magnetic fields.

9

Heating Curve for Water (a pure substance)

Water phase changes

constant
Temperature remains __________
during a phase change.

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Phase change diagram

Vaporization
or boiling

Exothermic Endothermic
(heat released) (heat absorbed)

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Physical changes . . .
change a substance WITHOUT
changing its chemical makeup.

After a physical change, you still have
the same substance, it is just in a
different form.

Examples:

boiling, freezing, melting, condensation

dissolving

split, crack, crush etc
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Physical properties ..
are qualities which can be observed without
changing the substance’s composition.

For example:

boiling point, freezing point, melting point

color hardness

density malleability, ductility

solubility conductivity

13

Chemical changes
Substances are
broken down in
chemical reactions
and new substances
are made.

Example - Burning hydrogen
(H2) with oxygen (O2) gives
H2O.

14

Chemical Properties describe the how
substances react chemically. For example:

Metals react in acid to produce H2 gas
Zn (s) + HCl (aq)  H2 (g) + ZnCl2 (aq)


In a CHEMICAL CHANGE, the composition of the
original substance(s) is altered.

The process of chemical change is described as a
chemical reaction.
chemical change
REACTANTS PRODUCTS

Different substances are present at the end of the
chemical change. The atoms in the reactants are
rearranged to make new and different products.

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Signs of a Chemical Change

 Color change
 Heat
 Light
 Gas Produced (not from boiling!)
 Precipitate – a solid formed by mixing
two liquids together

Physical vs. Chemical Properties

Examples
 melting point
 flammable
 density
 magnetic
 tarnishes in air

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Physical vs. Chemical Properties

Examples
 melting point physical
 flammable chemical
 density physical
 magnetic physical
 tarnishes in air chemical

19

Physical vs. Chemical Changes

 Examples:
 rusting iron
 dissolving in water
 burning wood
 melting ice
 grinding spices

20

Physical vs. Chemical Changes

 Examples:
 rusting iron chemical
 dissolving in water physical
 burning wood chemical
 melting ice physical
 grinding spices physical

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Matter (audio) r1

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Matter (audio) r1