ConcepTest: Isotopic Dating with Parent to Daughter Ratios
This material was originally created for
Starting Point:Introductory Geology and is replicated here as part of the SERC Pedagogic Service.
Initial Publication Date: May 8, 2006
Question:
The half-life of a radioactive isotope is 500 million years. Scientists testing a rock sample discover that the sample contains three times as many daughter isotopes as parent isotopes. What is the age of the rock?
a. 500 million years
b. 1,000 million years
c. 1,500 million years
d. 2,500 million years
a. 500 million years
b. 1,000 million years
c. 1,500 million years
d. 2,500 million years
Student Responses:
No data yet. The correct response is b.
If you would like to help acquire more Before and After statistics for this example, please contact the authors (see link at top of page).
References and Notes:
The use of ConcepTests and Peer Instruction is discussed in detail on the ConcepTest page.
McConnell, D.A., Steer, D.N. and Owens, K.A., 2003, Assessment and Active Learning Strategies for Introductory Geology Courses, Journal of Geoscience Education, 51(2), 205-216.
McConnell, D.A., Steer et al., 2006, Using Conceptests to Assess and Improve Student Conceptual Understanding in Introductory Courses, Journal of Geoscience Education, (54(1), 61-68.