1. All of the naturally occurring radioactive decay series end when the radioactive elements have decayed to

bismuth (Bi)
hydrogen (H)
lead (Pb)
uranium (U)

answer: Uranium (U)

2. This type of radiation can easily pass through a human.

gamma
ultra-violet
beta
alpha

answer: gamma

3. This type of radiation is really the nucleus of a helium atom.

alpha
gamma
beta
proton

answer: alpha

4. As the size of nuclei increases, the ratio of neutrons to protons in the band of stability increases to

3 to 1
1.25 to 1
2 to 1
1.5 to 1

answer: 1.5 to 1

4 answers

Ok except for #1. U is a radioactive element, naturally. There is a series for U-238, another series for U-235, and a third for Th-232. All end in Pb.
please need help thanks alot!!!!
Thanks DrBob222!
Mike--If you have a question, go to the top of the page and click on Post a New Question. Then type in your question and submit it. Someone will review it for you.