1. Assume you begin with 10g of a radioactive parent isotope. How many grams of the parent will remain after: One half-life Two half-lives Three half-lives Four half-lives 2. If a radioactive isotope has a half-life of 400 million years, how long will it take for 50% of the material to change to the daughter? Lyears How long will it take for 25% of the material to change to the daughter? Lyears 3. A sample is brought into the laboratory and the chemist determines the percentage of the parent isotope remaining is 12.5% of the original amount. If the half-life of the material is 600 million years, how old is the sample? Lyears 4. Determine the ages of a rock sample that contain a parent isotope with a half-life of 100 million years and have the following percentages: 50% Age:__/ 25% Age:_c 6.25% Age:

1. Assume you begin with 10g of a radioactive parent isotope. How many grams of the parent will remain after: One half-life Two half-lives Three half-lives Four half-lives 2. If a radioactive isotope has a half-life of 400 million years, how long will it take for 50% of the material to change to the daughter? Lyears How long will it take for 25% of the material to change to the daughter? Lyears 3. A sample is brought into the laboratory and the chemist determines the percentage of the parent isotope remaining is 12.5% of the original amount. If the half-life of the material is 600 million years, how old is the sample? Lyears 4. Determine the ages of a rock sample that contain a parent isotope with a half-life of 100 million years and have the following percentages: 50% Age:__/ 25% Age:_c 6.25% Age:

Inquiry into Physics

8th Edition

ISBN:9781337515863

Author:Ostdiek

Publisher:Ostdiek

Chapter11: Nuclear Physics

Section: Chapter Questions

Problem 17Q

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