Pd-100 has a half-life of 4 days. If one had 120g at the start, how much would be present after 20.0 days?

(a)  

Os-182 has a half-life of 21.5 hours. How many grams of a 10.0 gram sample would have decayed after exactly three half-lives?

(a)  

After 24.0 days, 2.00 milligrams of an original 128.0 milligram sample remain. What is the half-life of the sample?

(a)  

Fermium-253 has a half-life of 0.334 seconds. A radioactive sample is considered to be completely decayed after 10 half-lives. How much time will elapse for this sample to be considered gone?

(a)  

At time zero, there are 10.0 grams of W-187. If the half-life is 24 hours, how much will be present at the end of one day? Two days? Seven days?

(a)  

100.0 grams of an isotope with a half-life of 36.0 hours is present at time zero. How much time will have elapsed when 6.25 grams remains?

(a)  

How much time will be required for a sample of H-3 to lose 75% of its radioactivity? The half-life of tritium is 12.5 years.

(a)  

What is the half-life of the decay curve?

(a)  

What is the half-life of Carbon-14 according to the curve?

(a)