The half-lives of 235U and 238U are 7.04 × 108 years and 4.47 × 109 years, respectively, and the present abundance ratio is 238U>235U 5 137.7. It is thought that their abundance ratio was 1 at some time before our earth and solar system were formed about 4.5 × 109 years ago. Estimate how long ago the supernova occurred that supposedly produced all the uranium isotopes in equal abundance, including the two longest lived isotopes, 238U and 235U.

The half-lives of 235U and 238U are 7.04 × 108 years and 4.47 × 109 years, respectively, and the present abundance ratio is 238U>235U 5 137.7. It is thought that their abundance ratio was 1 at some time before our earth and solar system were formed about 4.5 × 109 years ago. Estimate how long ago the supernova occurred that supposedly produced all the uranium isotopes in equal abundance, including the two longest lived isotopes, 238U and 235U.

Modern Physics

3rd Edition

ISBN:9781111794378

Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Publisher:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Chapter13: Nuclear Structure

Section: Chapter Questions

Problem 46P

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