1. Chapter 4.1

2. Half-Life Original Sample One half-life Two half-lives Three half-lives Contains a certain One-half of the One-fourth of One-eight of the Amount of radioactive sample remains the sample remains sample remains

3. Half life Sample Problem One isotope of Iodine has a half-life of 8 days. That is, after 8 days, ½ of all the atoms in a given sample of the isotope will have undergone nuclear decay. Using a 1 gram sample. How much will remain after 8,16, and 32 days?

4. Finding a Date by Decay Finding the age of something thousands of years old can be difficult…. Scientists were able to determine the age of the Iceman. 5,300 years old Used the decay of radioactive carbon

5. Carbon 14- It’s in You!!!! Carbon atom is in every living thing Some are radioactive carbon 14 When an organism dies carbon 14 begins to decay

6. A steady Rate of Decay Every 5,370 years is the half life of carbon 14 Half Life: the amount of time it takes one-half of the nuclei of a radioactive isotope to decay