gcsescience.com 1 gcsescience.com
What is Radioactivity?
Sometimes the nucleus of an
atom is unstable.
A change will occur in the
nucleus to make it more stable.
The change is called a decay.
When a nucleus decays
it will emit
(give out) some particles or waves.
Emitting
particles or waves from the nucleus
is called radioactivity.
Radioactive decay is a random process which gives
out heat.
The particles or
waves that are emitted
(see below) are called
radiation.
The same word radiation is also used for some
electromagnetic
waves
which have not come from radioactive decay.
What are the Three
Types of Radioactivity?
There are three types of radioactivity,
called alpha,
beta
and gamma. A radioactive nucleus will emit either an
alpha particle or a
beta particle or a gamma
ray. After an
alpha particle or a
beta particle has been emitted from a
nucleus, the atomic
number of the atom will
have changed.
The atom will have changed
into a
different element.
An alpha or beta emitter might
also emit gamma
radiation.
Is Radioactivity
Good or Bad?
Radioactivity can be both harmful and useful.
For example, the rate of decay (called the half-life) can be used
to find out how old things
are. The energy released from
a nucleus during fission can be used to generate electricity.
Radioactivity can cause damage to living cells leading to cancer.
Links Radioactivity Revision Questions
gcsescience.com Physics Quiz Index Radioactivity Quiz gcsescience.com
Home GCSE Chemistry GCSE Physics
Copyright © 2015 gcsescience.com. All Rights Reserved.