# Radioactivity and radioactive dating

Certain highly excited short-lived nuclear states can decay through neutron emission, or more rarely, proton emission .Since it is a stochastic (random) process, the decay rate of a particular atom cannot be predicted, but it can be for a group of atoms of the same element and this is the basis of radiometric dating.This particular quality also makes them a good source for random variation when generating true random numbers.Different elements can have vastly different half lives.Skills: -critical thinking -data analysis -questioning -graphing and data collecting Vocab Words: 1. This activity can be adapted for older students, but is used in an 8th grade earth science classroom.Class size can vary, but activity should be done in groups of 2-3.

Then students take the class data and create a graph comparing the number of parent isotopes to the number of half-lives.Once all groups finish, each group records their info on the class decay table (on the board) and we calculate the averages of the class. Isotope Concepts: Students should begin to see the pattern that each time they dump out their M&Ms, about half become stable.Once this info is calculated, students create a graph comparing the class average of parent isotopes to the number of half-lives. Students will be able to explain what a half-life of a rock is. Students will have a more in-depth understanding of what radioactive decay is. Students will understand how scientists use half-lives to date the age of rocks. Students then should be able to see the connection of the M&Ms and radioactive elements in rocks, and how scientists can determine the age of rocks by looking at the amount of radioactive material in the rock.Convert half-life to mean lifetime or decay constant, and vice versa by entering any of the three values in its respective field.Our versatile radioactive decay calculator supports many different time units and automatically converts them if the time unit you measure the time elapsed is different than the time unit you enter the half-time, decay constant or mean lifetime in.