Page 29 - Science Course 1 (Book 2)

Matter: Physical Changes Mo7-L3a: What is Physical Change?

Lesson 3

During a physical change, the matter does not
become something different even though physical
properties change.
In this topic, you will learn the following
lessons:

Mo.7–L3a: What is Physical Change?

Mo7-L3a What is Physical Change?

KEY CONCEPTS:
1. How can a change in energy affect the state of
matter?
2. What happens when somthing dissolves?
3. What is meant by conversation of mass?

Vocabulary A-Z
Let us learn some vocabulary When thermal energy is added to a solid, the par-
ticles in the solid move faster and faster, and the
temperature increases.
Physical Change
When the particles are moving too fast for attractive
a change in the size, shape, form, or state of matter forces to hold them tightly together, the solid reach-
that does not change the matter’s identity.
es its melting point.

When the particles in a liquid are
moving so fast that attractive
forces cannot hold them close
together, the liquid reaches its
boiling point.

Sublimation occurs when a solid changes directly to
a gas without f rst becoming a liquid.
Physical Changes

A physical change is a change in size, shape, form,
or state of matter in which the matter’s identity stays
the same.

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