(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A small animal bone fragment found in an archaelogical site has a carbon mass of 155g. When the animal was alive, the ratio of radioactive^{14}_{6}C to the stable^{12}_{6}C was 1.31×10^{-12}. What was the number of^{14}_{6}C nuclei found in the sample when the animal was alive?

2. Relevant equations

None given, but I would assume:

N=N_{0}e^{-λt}

3. The attempt at a solution

Not too sure where to start so I got the decay constant, λ by using half life of Carbon14, 5730 Years

0.5=e^{-λ(5730)}

λ=1.21×10^{-4}

Then I solved the for the number of years since the animal was alive by plugging everything back into the original equation, assuming N/N_{0}= 1.31×10^{-12}

t=-ln(1.31×10-12)/-1.21×10^{-4}= 226180 Years

Up until here I don't think I did anything wrong, but here is where I am unsure of what to do.

I tried using the same formula to solve for N_{0}, but this time using the given 155g.

155=N_{0}e^{-(1.2110-4)(226180)}

N_{0}=1.18×10^{14}g

I don't think in doing the right thing here. Can anyone give me some guidance?

Thanks!

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# Homework Help: Finding Original Carbon nuclei from given sample.

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