ConcepTest: Calculating Rock Age from Parent Radioactive Isotope
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:
A radioactive (parent) isotope of element X is discovered in different amounts in four rocks (A, B, C, D) of the same composition. Which rock has the oldest calculated age?
a. 15% of element X remains in Rock A
b. 57% of element X remains in Rock B
c. 28% of element X remains in Rock C
d. 75% of element X remains in Rock D
a. 15% of element X remains in Rock A
b. 57% of element X remains in Rock B
c. 28% of element X remains in Rock C
d. 75% of element X remains in Rock D
Student Responses:
No data yet. The correct response is d.
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