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uzumi99

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« on: February 21, 2022, 11:24:25 AM »
Hello,

Sorry if this in the wrong forum. I needed a little bit of help with an assignment.

The question is asking me determine the length of a half-life (t 1/2) for the U-238 to Pb-206 parent-daughter pair. Assuming I have 1,000 atoms of U-238 and 0 atoms of Pb-206 at t0, how many atoms will I have after one, two, three, and four half-lives?

I also feel like I might be vastly over complicating this in my head.

Now, my assumption is that after one half-life (4.468 billion-ish years), I'll have 500 U atoms and 500 Pb atoms. The second half-life is another 4.468 billion years later (8.936 total) leaving us with 250 U and 750 Pb, third half-life (13.4 by) will equal 125 U and 875 Pb, and the fourth half life (17.872 billion) will leave us with 62.5 (63?) Uranium atoms and 937 Lead atoms.

Is that correct or am I mistaken?

Babcock_Hall

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« Reply #1 on: February 21, 2022, 08:16:05 PM »
I did not see any problems with what you wrote.

sjb

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« Reply #2 on: February 22, 2022, 01:46:53 AM »

Enthalpy

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