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The number of <sup>238</sup> U atoms in ...

The number of 238 U atoms in an ancient rock equals the number of 206 Pb atoms. The half-life of decay of 238 U is 4.5x109 years. Estimate the age of the rock assuming that all the 206 Pb atoms are formed from the decay of 238U.

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To estimate the age of the rock based on the given information, we can follow these steps: ### Step 1: Understand the relationship between Uranium and Lead We know that the number of \(^{238}U\) atoms equals the number of \(^{206}Pb\) atoms in the rock. This means that all the lead atoms present in the rock have been formed from the decay of uranium atoms. ### Step 2: Set up the initial conditions Let \(N_0\) be the initial number of \(^{238}U\) atoms at time \(t = 0\). After some time \(t\), the number of \(^{238}U\) atoms remaining will be \(N\), and the number of \(^{206}Pb\) atoms formed will be \(N_0 - N\). ...
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