ConcepTest: Oldest Rock Dating #1
Question:
The world's oldest known rock is approximately 4 billion (4,000 million) years old. What are the approximate relative percentages of parent and daughter isotopes for Uranium-238 and Lead-206 (half-life = 4.5 billion years)?
a. 75% parent & 25% daughter
b. 45% parent & 55% daughter
c. 55% parent & 45% daughter
d. 25% parent & 75% daughter
a. 75% parent & 25% daughter
b. 45% parent & 55% daughter
c. 55% parent & 45% daughter
d. 25% parent & 75% daughter
Student Responses:
No data yet. The correct response is d.
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