Isotopes elements used radioactive dating
The alkali metals are the elements that make up Group 1 (IA) of the periodic table.The periodic table is a chart that shows how chemical elements are related to one another.The first lesson, Isotopes of Pennies, introduces the idea of isotopes.The final lesson, Frosty the Snowman Meets His Demise: An Analogy to Carbon Dating, is based on gathering evidence in the present and extrapolating it to the past.(See sidebar on Davy in the calcium entry in Volume 1.) There are very few uses for potassium as a pure element.However, compounds of potassium have many important applications, the most important of which is as a fertilizer.It is estimated to require four hours of class time, including approximately one hour total of occasional instruction and explanation from the teacher and two hours of group (team) and individual activities by the students, plus one hour of discussion among students within the working groups.
The electrical current breaks the compound into its elements.
More than ten million compounds of carbon are known.
No other element, except for hydrogen, occurs in even a fraction of that number of compounds.
To demonstrate that the rates of decay of unstable nuclei can be measured, that the exact time that a certain nucleus will decay cannot be predicted, and that it takes a very large number of nuclei to find the rate of decay.
This is the second lesson in a three-lesson series about isotopes, radioactive decay, and the nucleus.
The alkali metals also include lithium, sodium, rubidium, cesium, and francium. Potassium is so active that it never occurs free in nature.