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inysia [295]
3 years ago
7

A meteorite is determined to be 4.5 billion years old. It now has 78 atoms of lead-206. Assuming no loss of daughter isotopes, h

ow many atoms of uranium-238 did the meteorite have to begin with? The half-life of uranium-238 is 4.5 billion years.
a) 156
b) 312
c) 78
d) 238
Biology
1 answer:
vovangra [49]3 years ago
6 0
Given the age of the meteorite is 4.5 billion years old with 78 atoms of lead-206 the answer should be B. 156. The half-life of uranium-238 in order to decay into lead-206 is 4.46 billion years, which means that the original number of atoms is 156.  
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