Radioactive Decay: Calculating Plutonium Amount & Age of Meteor

In summary, we are calculating the number of plutonium molecules and the time since a meteor containing 2.45kg of plutonium-239 struck the Earth. Using the formula no.atoms= mass/(atomic mass) x avagadro's no.(6.02x10^23), we determined that there are currently 6.16979x10^24 particles present. To calculate the time, we use the equation N = No e^(-γt) where the decay constant, γ, is related to the half-life, T1/2, by γT1/2 = ln(2). Further calculations are needed to obtain a value for γ and solve for t.
  • #1
CharlieW95
3
0

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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  • #2
just obtain a value for γ, substitute it into N = No e^(-γt) and solve for t
 

1. How do you calculate the amount of plutonium in a sample?

The amount of plutonium in a sample can be calculated using the equation N = N0e-λt, where N is the current amount of plutonium, N0 is the initial amount, λ is the decay constant, and t is the time that has passed since the initial amount was measured.

2. What is the decay constant?

The decay constant, denoted by λ, is a measure of how quickly a radioactive substance decays. It is unique to each radioactive isotope and is used in the calculation of the amount of a substance remaining after a certain amount of time.

3. How can the age of a meteor be determined using radioactive decay?

The age of a meteor can be determined by measuring the amount of radioactive isotopes, such as plutonium, present in the meteor and using the radioactive decay equation to calculate how much time has passed since the initial amount was formed.

4. What factors can affect the accuracy of calculating the age of a meteor using radioactive decay?

The accuracy of calculating the age of a meteor using radioactive decay can be affected by several factors, including the initial amount of radioactive isotopes present, the decay constant, and any external factors that may have altered the amount of radioactive material in the meteor since its formation.

5. How is radioactive decay used in dating geological formations?

Radioactive decay is used in dating geological formations by measuring the amount of radioactive isotopes present in the rocks or fossils and using the decay equation to calculate the age of the formation. This method is often used to determine the age of Earth's rocks and can provide valuable information about the history of our planet.

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