State of Matter, U1L5

States of Matter

Unit 1: Matter

STATES OF MATTER

In this lesson, you will
learn about the states of
matter and how particles
move in a solid, liquid, and
gas state.

STATES OF MATTER

All matter is in constant
motion.

STATES OF MATTER

Why do particles in a solid
state not move freely?

STATES OF MATTER

In solids, particles vibrate
in place, close together
and do not move freely.

STATES OF MATTER

The particles are like this because
their thermal energy is less than
that of their liquid or gas states,
so they have a greater attraction
to each other.

Multiple Choice

Why do the particles in solids vibrate in a fixed, close position?

• The particles have a weak attraction

• The particles have more thermal energy than liquids

• The particles have less thermal energy than liquids

• The particles have more thermal energy than gases

STATES OF MATTER

How do the particles in
liquids move?

STATES OF MATTER

The particles in liquids are
not in a fixed place so they
can slide past each other
freely.

STATES OF MATTER

The particles are like this because
their thermal energy is less than
that of their gas state, but greater
than their solid state, so their
attraction to each other is
different.

Multiple Choice

How do particles in liquids move?

• They vibrate in a fixed position

• They move freely

• They slide past one another

STATES OF MATTER

How do particles in a gas
state move?

STATES OF MATTER

There is more space between
gas particles than between
particles in a liquid or solid,
so they can move easily in
any direction.

STATES OF MATTER

The particles are like this because
their thermal energy is greater
than their solid or liquid states, so their attraction to each other is
less.

Multiple Choice

Why is the attraction between gas particles so weak?

• The attraction is weak because the particles are smaller.

• The attraction is weak because there is more thermal energy.

• The attraction is weak because there is less thermal energy.

• The attraction is weak because the particles are larger.

STATES OF MATTER

Solids, liquids, and gases
have certain properties
based on particle motion.

STATES OF MATTER

Solids have a definite
volume and shape.

STATES OF MATTER

Liquids have a definite
volume but can change
shape.

STATES OF MATTER

Gases can change in
volume and shape.

Multiple Choice

Which state of matter has a definite volume and a definite shape?

• gas

• solid

• liquid

STATES OF MATTER

When substances change state,
they do not change chemically.
The change is only physical, and
what changes are the motion of
the molecules and the amount of
space between them.

Multiple Choice

A change in state is a ______.

• change in particle size.

• change in the identity of the substance.

• change in particle motion and the space between the particles.

STATES OF MATTER

When substances lose or gain energy, either the temperature of the substance changes, or its state changes.

STATES OF MATTER

However, both a temperature change or a change of state cannot occur at the same time.