1. Section 1: Nuclear Radiation
Under certain conditions, some nuclei can emit alpha, beta, or gamma radiation. K
What I Know W
What I Want to Find Out L
What I Learned

2. 12(A) Describe the characteristics of alpha, beta, and gamma radiation.
3(F) Research and describe the history of chemistry and contributions of scientists.
Copyright © McGraw-Hill Education
Nuclear Radiation

3. Essential Questions How was radioactivity discovered and studied?
What are the key properties of alpha, beta, and gamma radiations?
Copyright © McGraw-Hill Education
Nuclear Radiation

4. Vocabulary Review New nucleus radioisotope X-ray penetrating power
Nuclear Radiation
Copyright © McGraw-Hill Education

5. The Discovery of Radiation
Nuclear chemistry is concerned with the structure of atomic nuclei and the changes they undergo.
Nuclear reactions are different from other types of reactions.
Marie Curie and her husband Pierre isolated the first radioactive materials.
Table 1 Comparison of Chemical and Nuclear Reactions
Chemical Reactions
Nuclear Reactions
Occur when bonds are broken and formed
Involve only valence electrons
Associated with small energy changes
Atoms keep the same identity although they might gain, lose, or share electrons, and form new substances
Temperature, pressure, concentration, and catalysts affect reaction rates
Occur when nuclei combine, split, and emit radiation
Can involve protons, neutrons, and electrons
Associated with large energy changes
Atoms of one element are often converted into atoms of another element
Temperature, pressure, and catalysts do not normally affect reaction rates
Nuclear Radiation
Copyright © McGraw-Hill Education

6. Types of Radiation
Isotopes of atoms with unstable nuclei are called radioisotopes.
Unstable nuclei emit radiation to attain more stable atomic configurations in a process called radioactive decay.
The three most common types of radiation are alpha, beta, and gamma.
Copyright © McGraw-Hill Education
Nuclear Radiation

7. Types of Radiation
Alpha particles have the same composition as a helium nucleus—two protons and two neutrons.
Because of the protons, alpha particles have a 2+ charge.
Alpha radiation consists of a stream of particles.
Alpha radiation is not very penetrating—a single sheet of paper will stop an alpha particle.
Copyright © McGraw-Hill Education
Nuclear Radiation

8. Types of Radiation
Beta particles are very fast-moving electrons emitted when a neutron is converted to a proton.
Beta particles have insignificant mass and a 1– charge.
Beta radiation is a stream of fast moving particles with greater penetrating power—a thin sheet of foil will stop them.
Copyright © McGraw-Hill Education
Nuclear Radiation

9. Types of Radiation
Gamma rays are high-energy electromagnetic radiation.
Gamma rays have no mass or charge.
Gamma rays almost always accompany alpha and beta radiation.
X rays are a form of high-energy electromagnetic radiation emitted from certain materials in an excited state.
The ability of radiation to pass through matter is called its penetrating power.
Gamma rays are highly penetrating because they have no charge and no mass.
Copyright © McGraw-Hill Education
Nuclear Radiation

10. Review Essential Questions Vocabulary
How was radioactivity discovered and studied?
What are the key properties of alpha, beta, and gamma radiations?
Vocabulary
radioisotope
X-ray
penetrating power
Nuclear Radiation
Copyright © McGraw-Hill Education