CHEM - Uranium isotope relative abundance at diff times

Click For Summary
SUMMARY

The discussion focuses on calculating the relative abundances of uranium isotopes (238U, 235U, and 234U) at the time of Earth's formation, approximately 4.6 billion years ago. The current abundances are 99.2745% for 238U, 0.7196% for 235U, and 0.0055% for 234U. Participants emphasize the importance of knowing the half-lives of these isotopes and applying the equation t = age = 1/lambda * ln(N/No) to determine past ratios. The conversation encourages clear communication to avoid redundancy in questions and answers.

PREREQUISITES
  • Understanding of radioactive decay and half-lives
  • Familiarity with the natural logarithm and its applications in decay equations
  • Basic knowledge of uranium isotopes and their significance in geology
  • Proficiency in algebra for manipulating decay equations
NEXT STEPS
  • Research the half-lives of uranium isotopes, specifically 238U, 235U, and 234U
  • Study the application of the decay equation N = No*e^lambda*t in geological contexts
  • Explore the implications of uranium isotope ratios in radiometric dating
  • Investigate the role of uranium isotopes in Earth's formation and early geological history
USEFUL FOR

Geologists, nuclear physicists, students studying radiometric dating, and anyone interested in the historical abundance of uranium isotopes in Earth's crust.

thiev
Messages
2
Reaction score
0
1. Homework Statement

The relative abundance of uranium isotopes in today’s Earth crustal material is:
99.2745% 238U
0.7196% 235U
0.0055% 234U
What were the relative abundances when the Earth was formed 4.6x109 years ago?


2. Homework Equations

t = age = 1/lambda * ln(N/No)

N = No*e^lambda*t

3. The Attempt at a Solution

i don't know how to approch this...
 
Physics news on Phys.org
Hey,

I agree with LowlyPion in the other post that you need to know the half-lives and then I think it will be a matter of ratios.

Just post a question the once for the future. This is so people helping you are seeing what everyone is saying and not repeating work that has already been done. We only want to help. :biggrin:

The Bob
 

Similar threads

Uranium isotope relative abundance at diff times
  • · Replies 1 ·
Replies
1
Views
3K
How Is Uranium Isotope Enrichment Achieved Through Effusion?
  • · Replies 1 ·
Replies
1
Views
2K
Abundancy of Uranium 235 when the earth was formed.
  • · Replies 4 ·
Replies
4
Views
4K
Ratio of rms speeds of two isotopes
  • · Replies 1 ·
Replies
1
Views
5K
Calculating the Isotope Ratio of Uranium 235 and 238 4.5 Billion Years Ago
  • · Replies 4 ·
Replies
4
Views
2K
Age of Sample: U-235 & U-238 Abundances
  • · Replies 2 ·
Replies
2
Views
2K
Possible title: Isotope Abundance Calculations: Where Did I Go Wrong?
  • · Replies 9 ·
Replies
9
Views
12K
How can I calculate sieverts from the activity of depleted uranium?
  • · Replies 7 ·
Replies
7
Views
6K
Ageing of the universe using percentages of Uranium?
  • · Replies 2 ·
Replies
2
Views
2K
Nuclear u-235 and u-238 isotope half life question
  • · Replies 3 ·
Replies
3
Views
8K