1. Chapter 9 Nuclear Radiation
9.1
Natural Radioactivity

2. Stable and Radioactive Isotopes
A radioactive isotope
has an unstable nucleus
emits radiation to become more stable, changing the composition of the nucleus
is identified by the mass number of the isotope

3. Nuclear Radiation
Nuclear radiation is the radiation emitted by an unstable atom and takes the form of alpha particles, neutrons, beta particles, positrons, or gamma rays.

4. Types of Radiation Alpha () particle is two protons and two neutrons.
Beta () particle is a high-energy electron.
Positron (+) is a positive electron.
Gamma rays are the high-energy radiation released from a nucleus when it decays.

5. Learning Check
Give the name and symbol for the following types of radiation.
A. alpha radiation
B. radiation with a mass number of 0 and atomic number of +1
C. radiation that represents high-energy radiation released from the nucleus

6. Solution
Give the name and symbol for the following types of radiation.
A. alpha radiation
B. radiation with a mass number of 0 and
atomic number of +1
C. radiation that represents high-energy
radiation released from the nucleus

7. Radiation Protection Radiation protection requires
paper and clothing for alpha particles
a lab coat or gloves for beta particles
a lead shield or a thick concrete wall for gamma rays
limiting the amount of time spent near a radioactive source
increasing distance from the source

8. Shielding for Radiation Protection

9. Learning Check What type of radiation will be blocked by
A. lead shield
B. paper, clothing

10. Solution What type of radiation will be blocked by
A. lead shield gamma radiation
B. paper, clothing alpha radiation