earth

posted by .

how long will it take Uranium-238 for there to ne 25% of the original radioactive period to be left? i need this question answered ASAP!!!!!(:

  • earth -

    8 billion year

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    Uranium-235 can be separated from U-238 by fluorinating the uranium to form UF6 (which is a gas) and then taking advantage of the different rates of effusion and diffusion for compounds containing the two isotopes. Calculate the ratio …
  2. Chemistry *URGENT*

    URGENT help! 3. A rock sample was dated using potassium-40, Neasyrenebt ubducated tgat 1/8 of the original parent isotope is left in the rock sample. How old is the rock?
  3. Calculus disaster

    Uranium ore has two main isotopes, mostly U-238 with just a trace amount of U-235. In a sample of Uranium ore, 99.85% of the atoms are U-238 atoms and 0.15% are U-235 atoms. Before the Uranium can be used in a nuclear power plant, …
  4. geology

    How old are the oldest meteorites yet studied and what is the minimum age of Earth since Earth is at least as old as the meteorites. We know the oldest meteorites contain equal amounts of uranium 238 and lead 206. Uranium 238 has a …
  5. Chem 2

    The half-life for the radioactive decay of U-238 is 4.5 billion years and is independent of initial concentration. a) How long will it take for 10% of the U-238 atoms in a sample of U- 238 to decay?
  6. Chemistry 1046

    Geologists can estimate the age of rocks by their uranium-238 content. The uranium is incorporated in the rock as it hardens and then decays with first-order kinetics and a half-life of 4.5 billion years. A rock contains 65.7% of the …
  7. Chemistry

    Uranium-235 can be separated from U -238 by fluorinating the uranium to form UF 6 which is a gas) and then taking advantage of the different rates of effusion and diffusion for compounds containing the two isotopes. Calculate the ratio …
  8. Chemistry

    Geologists can estimate the age of rocks by their uranium-238 content. The uranium is incorporated in the rock as it hardens and then decays with first-order kinetics and a half-life of 4.5 billion years. A rock is found to contain …
  9. Science

    Uranium-238 is less stable than oxygen-16. What accounts for this difference?
  10. college math

    the half life of Uranium -238 is 4.5 billion years and the age of earth is 4.5 X 109 years. What fraction of Uranium-238 that was present when earth was formed still remains?

More Similar Questions