http://www.ck12.org Chapter 3. Chemical Interactions
Summary
- Many elements have one or more isotopes that are radioactive. These isotopes are called radioisotopes. An
example of a radioisotope is carbon-14. - The nuclei of radioisotopes are unstable, so they constantly decay and emit radiation.
- In elements with more than 83 protons, all of the isotopes are radioactive.
Vocabulary
- radioisotope: Radioactive isotope, or isotope that emits radiation from its nucleus.
Explore More
Watch the video about radioisotopes at the following URL, and then answer the questions below. http://www.youtu
be.com/watch?v=B54tMbdKqNM
MEDIA
Click image to the left for use the URL below.
URL: http://www.ck12.org/flx/render/embeddedobject/82381- Describe the analogy in the video for stable and radioactive isotopes.
- Complete the following table 3.12:
TABLE3.12:Practice
Atomic Number Proton-to-Neutron Ratio for a Stable Nucleus
1 - 19
20 –82
>82- How can radioisotopes become stable? List three ways and state when each way occurs.
Review
- What is a radioisotope? Give an example.
- Why do radioisotopes have unstable nuclei?
- Which elements in the periodic table have only radioactive isotopes?