(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Initially, a particular sample has a total mass of 200 grams and contains 256 x 1010 radioactive nuclei. These radioactive nuclei have a half life of 1 hour.

(a) After 3 hours, how many of these radioactive nuclei remain in the sample (that is, how many have not yet experienced a radioactive decay)? Note that you can do this problem without a calculator

(b) After that same amount of time has elapsed, what is the total mass of the sample, to the nearest gram?

2. Relevant equations

.5 ^(time/half life)

and then multiply that to initial amount

3. The attempt at a solution[/b

i got part A by dividing the initial amount by 8. I tried doing the same for part B but I keep getting it wrong

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# Homework Help: Half life problem

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