Radioactive Decay: Calculating Plutonium Amount & Age of Meteor

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SUMMARY

The discussion focuses on calculating the amount of plutonium-239 in a meteor and determining the time since it struck Earth. The meteor contains 2.45 kg of plutonium-239, which has a half-life of 24,065 years. The number of plutonium molecules currently present is calculated using the formula for the number of atoms, resulting in approximately 6.16979 x 1024 particles. To find the time since the meteor struck, the decay constant (γ) must be calculated and substituted into the equation N = N0 e-γt.

PREREQUISITES
  • Understanding of radioactive decay and half-life concepts
  • Familiarity with Avogadro's number (6.02 x 1023)
  • Knowledge of the exponential decay formula N = N0 e-γt
  • Basic skills in logarithmic functions and natural logarithms
NEXT STEPS
  • Calculate the decay constant (γ) for plutonium-239 using γT1/2 = ln(2)
  • Apply the decay formula N = N0 e-γt to solve for time (t)
  • Explore the implications of half-life in radioactive dating techniques
  • Research the properties and applications of plutonium-239 in various fields
USEFUL FOR

Students studying nuclear physics, chemistry enthusiasts, and professionals involved in radiometric dating or nuclear material analysis will benefit from this discussion.

CharlieW95
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Homework Statement



A meteor contains 2.45kg of plutonium-239. It has a half-life of 24065 years. Calculate:
a) The number of plutonium molecules currently present in the meteor (at. mass = 239.052)
b) How long ago the meteor struck the Earth if originally it contained 10kg of plutonium.


Homework Equations


no.atoms= mass/(atomic mass) x avagadro^' s no.(6.02x〖10〗^23)

N = No e-γt
where the decay constant, γ(gamma), and T1/2 are related by
γT1/2 = ln(2)


The Attempt at a Solution


I solved A, and achieved an answer of 6.16979x1024 particles.
I'm confused as to where to go from here.
 
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just obtain a value for γ, substitute it into N = No e^(-γt) and solve for t
 

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