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FIND OUT MORE. Atoms 157 • Energy 166 • Forces 164 • Heat 168–169 • Motion 165 • Universe 26

Dust, living things, oceans, mountains, and planets –

everything you can touch is made from matter. With

electron microscopes scientists can see that all matter

is made from particles – tiny specks of matter that stick

together like crystals in a cube of sugar.

WHAT ARE FUNDAMENTAL PARTICLES?

Matter is built from particles. The smallest particles

are fundamental particles. Scientists have discovered

two kinds of fundamental particle — quarks and

leptons. Evidence for quarks and leptons is found by

smashing together larger particles at very high speeds.

The particles split and new particles are formed.

WHERE DOES MATTER COME FROM?

All matter in the Universe was created by the Big

Bang 14 billion years ago. In less than a second, the

Universe was filled with vast amounts of energy, such

as light and heat. The explosion made the Universe

expand. As it expanded, it cooled, and particles with

. MASS formed and clumped together.

WHAT ARE STATES OF MATTER?

Most matter on Earth exists in one of three states —

solid, liquid, or gas. In a solid, the particles are packed

closely together in a rigid pattern. In a liquid, the

particles are touching, but tumble freely over each

other. In a gas, the particles are widely spaced and

move about at random.

CAN MATTER BE DESTROYED?

Matter can be destroyed by changing its mass

into pure energy. This can happen when a particle

of matter collides with a particle of antimatter. The

matter and antimatter annihilate (destroy) each

other, and vanish as a flash of radiation.

Mass is the amount of matter an object contains. All objects with

mass have inertia (a force is needed to start, stop, or change their

motion), and are attracted to each other by the force of gravity.

PLASMA 3
A fourth state of matter forms
when matter is heated to very
high temperatures — like the
flame of a welding torch. Plasma
glows brightly. Stars and the
hottest parts of flames are made
from matter in the plasma state.

MASS

1 LIQUID

When the temperature rises above 0°C

(32°F) ice melts to liquid water. This is

water’s normal state over most of the Earth.

1 GAS

The hot steam shooting from a geyser is

water in the gas state. Water boils at 100°C

(212°F), changing from liquid to gas.

4 BIG BANG

The Universe is still expanding

and cooling today. As it cools,

the force of gravity draws

floating particles of matter

together to form new stars

and galaxies.

PARTICLE TRACKS 3

In a particle accelerator,

physicists investigate high-energy

collisions between particles. Some

particles are destroyed and some

are created. Their tracks spread

out from the point of impact.

Matter

Water

molecule

1 SOLID
Ice is water in the solid state. The ice
in this iceberg is at a temperature of 0°C
(32°F) or below.

matter