20.2. Half Life http://www.ck12.org
- There are two equal amounts of radioactive material. One has a short half-life and the other has a very long
half-life. If you measured the decay rates coming from each sample, which would you expect to have a higher
decayrate? Why?
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4. a. SubstanceAdecays faster thanBb. SubstanceBbecause there is more material left to decay.
5. a. 5× 1024 atoms b. Decay of a lot of atoms in a short period of time c. 2. 5 × 1024 atoms d.^12 e. 26.6 minutes
6. a. SubstanceB= 4 .6 g and substanceA= 0 .035 g b. substanceB
7. 1.2 g
8. 125 g
9. 0.46 minutes
10. The one with the short half life, because half life is the rate of decay.