Chemistry
posted by Sanjay .
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 halflife of each of the isotopes. Surely you have a text or notes that will furnish this. Co60 is the only one I know from memory for I worked with it many years ago. It is 5.1 years halflife. 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.
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