1. Slide 1 of 21 © Copyright Pearson Prentice Hall Nuclear Radiation > Types of Radiation (copy table into journal) 25.1

2. Slide 2 of 21 © Copyright Pearson Prentice Hall Nuclear Radiation > Radioactivity III. Radioactivity A. Marie Curie (1867-1934) and Pierre Curie (1859-1906) were able to show that rays emitted by uranium atoms caused fogging in photographic plates. 1. Marie Curie named the process by which materials give off such rays radioactivity. 2. The penetrating rays and particles emitted by a radioactive source are called radiation. 25.1

3. Slide 3 of 21 © Copyright Pearson Prentice Hall Nuclear Radiation > Radioactivity B. Nuclear reactions differ from chemical reactions in a number of important ways. 1. In chemical reactions, atoms tend to attain stable electron configurations by losing or sharing electrons. 2. In nuclear reactions, the nuclei of unstable isotopes, called radioisotopes, gain stability by undergoing changes. 25.1

4. Slide 4 of 21 © Copyright Pearson Prentice Hall Nuclear Radiation > Types of Radiation a. Alpha radiation: consists of helium nuclei called alpha particles, two protons and two neutrons and have a plus 2 positive charge. 25.1 3. There are three main types of nuclear radiation

5. Slide 5 of 21 © Copyright Pearson Prentice Hall Nuclear Radiation > Types of Radiation b. Beta Radiation: An electron resulting from the breaking apart of a neutron in an atom, called a beta particle. i. Carbon-14 emits a beta particle as it undergoes radioactive decay to form nitrogen-14. 25.1

6. Slide 6 of 21 © Copyright Pearson Prentice Hall Nuclear Radiation > Types of Radiation c. Gamma Radiation: high-energy photon is called a gamma ray, electromagnetic radiation. 25.1

7. Slide 7 of 21 © Copyright Pearson Prentice Hall Nuclear Radiation > Types of Radiation i. Alpha particles are the least penetrating. ii. Gamma rays are the most penetrating. 25.1

8. © Copyright Pearson Prentice Hall Slide 8 of 21 25.1 Section Quiz. 1.Certain elements are radioactive because their atoms have a.more neutrons than electrons. b.an unstable nucleus. c.a large nucleus. d.more neutrons than protons.

9. © Copyright Pearson Prentice Hall Slide 9 of 21 25.1 Section Quiz. 2.An unstable nucleus releases energy by a.emitting radiation. b.thermal vibrations. c.a chemical reaction. d.giving off heat.

10. © Copyright Pearson Prentice Hall Slide 10 of 21 25.1 Section Quiz. 3.Which property does NOT describe an alpha particle? a.2+ charge b.a relatively large mass c.a negative charge d.low penetrating power

11. © Copyright Pearson Prentice Hall Slide 11 of 21 25.1 Section Quiz. 4.When a radioactive nucleus releases a high- speed electron, the process can be described as a.oxidation. b.alpha emission. c.beta emission. d.gamma radiation.