1. Using the Chart of the Nuclides in the attached image below, select a nuclide that is radioactive and decays (changes) to another nuclide by emitting an alpha particle. Is the new element radioactive and if it is, how do you know that?

2. If the new nuclide is radioactive, what does it decay to?

3. Do the same thing with a nuclide that emits a beta particle.

4. If a rock contains 75% lead 206 (Pb206) and 25% uranium 238 (U238), how old is the rock? Explain how you determined the answer.