Monday
July 28, 2014

Homework Help: Chemistry *URGENT*

Posted by Anon on Friday, March 5, 2010 at 4:49am.

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?

5. When a sample of lava solidfied, it contained 28g of uranium-238. It that lava sample was later found to contain only 7g of uranium-238, how many years had passed since the lava solidified?

6. AFter 25 years, the number of radioactive cobalt atoms in a sample is reduced to 1/32 of the original count. What is the half-life of this isotope?

How would you find the answers to these questions?
TEll me the steps.

Thank you very much.

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

Radioactivity - 1. A granite rock is thought to be about 2 billion years old. ...
College Geology - assume that a particular radioactive-isotope has a half-life ...
geo/science - could you please tell me if this is the correct formula for ...
earth space science - Potassium-40 has a half-life of approximately 1.25 billion...
Geology - If a rock contains an isotope with a half live of 600 million years, ...
Physics - If a sample of a radioactive isotope has a half-life of 5 year(s), how...
Geology - Hi there I'm having trouble with this study guide. Could someone ...
Calculus Help Please Urgent!!! - At time t=0, an astronaut stands on a platform ...
chemistry help! - Potassium has an atomic mass of 39.10amu. a sample of ...
Chemistry - 0.12 g of rock salt(NaCl and impurities) was dissolved in water and ...

Search
Members