Posted by **Sanjay** on Saturday, March 3, 2007 at 8:50pm.

Which radioactive sample would contain the greatest remaining mass of the radioactive isotope after 10 years?

A. 2.0 grams of 198 Au

B. 2.0 grams of 42 K

C. 4.0 grams of 32 P

D. 4.0 grams of 60 Co

By the way the numbers next to the elements are their atomic masses. thanks again

You must look up the half-life of each of the isotopes. Surely you have a text or notes that will furnish this. Co-60 is the only one I know from memory for I worked with it many years ago. It is 5.1 years half-life. Then half of the mass will remain after 1 half life, 1/4 will remain after two half lives, etc.

You can also use

ln(No/N)=kt I can help with that if you need help after you obtain the half lives.

## Answer This Question

## Related Questions

- calculus - The rate at which an amount of a radioactive substance decays is ...
- AP Calculus - An Initial amount of 100 grams of Thorium-234 decays according to ...
- science - suppose you had two samples of the same radioactive isotope. one ...
- Calculus - The quantity Q of radioactive carbon remaining in a 200-gram wood ...
- chemistry - A radioactive sample contains 2.45 g of an isotope with a half-life...
- chemistry - A radioactive sample contains 2.45g of an isotope wiht a half life ...
- Math - How do I solve this if there is no equation to this 1. The population of ...
- science - If a radioactive isotope has a half life of 10 years and you start ...
- earth science - what would be the chart to use for carbon 14 whcih has a half ...
- chemistry -- radioactive decay - suppose you have a 150 gram sample of ...

More Related Questions