Dating rocks using radioactive decay
The first post question caused some confusion: Why didn't each group get the same results?A lot of the students said because they shook the containers differently... I also have students wash their hands before the activity, because of course after, the students eat the M&Ms. Radioactive decay and half-lives can be a very difficult concept for our 8th graders to grasp.Once students are in their groups, with supplies, and general directions are given, they are on their own for doing their runs.Students will record the number of M&Ms that are still "radioactive" (M side up) in their data table after each run, and set aside the "stable" (M side down) M&Ms.They not only enjoyed this activity, but they really gained a better understanding of it as well. Many of us believed that string theory was a very dramatic break with our previous notions of quantum theory.They were missing something absolutely fundamental. We are missing perhaps something as profound as they were back then.
By the mid-1940s, Willard Libby realized that the decay of C research—his life’s work—Libby was awarded the Nobel Prize in Chemistry in 1960, and the age of radioactive dating was born.The protons and neutrons form the nucleus of an atom with approximate diameters ranging from 1.75 fm for the hydrogen atom to 15 fm for the uranium atom.The chemical properties of each element are defined by the number of protons it contains in its nucleus and, consequently, the number of corresponding electrons that orbit it.Students should recognize each time the number should go down by appx half.Then students take the class data and create a graph comparing the number of parent isotopes to the number of half-lives.