Unit 7 Homework

Unit 7 homework 1) Convert bismuth-210 from hyphen notation to nuclear notation. 2) Convert 56Fe from nuclear notation to hyphen notation. 3) Isolated protons and neutrons have masses of 1.007825 amu and 1.008665 amu respectively. Yet a hydrogen-2 nuclide has a mass of 2.014102 amu which is less than the sum of the mass of a proton and a neutron (2.01649 amu). Explain this. 4) What might cause a nucleus to be unstable and eventually decay? 5) Balance the nuclear equation below: 208 82

62 Pb + 28 Ni → ___

Balance each of the following reactions and identify the reaction type as alpha decay, beta decay, electron capture, or positron emission 6) ____________________

226 88

Ra → ___+ 24He

7) ____________________

210 85

At + −01___ → ___

8) ____________________

33 15

9) ____________________

210 85

33 P →16 ___ + ___ 0 At → __ 84 ___ + __ ___

10) Define “half-life”. 11) Write out the decay series beginning from bismuth-210 until it reaches the stable Lead-206. 12) If a sample of iodine-131 decays from 60 mg to 7.5 mg in 24 day, what is its half life? 13) How long will it take a 1.28 gram sample of polonium-208 to decay to a mass of 0.160 grams assuming the half-life of polonium-208 is 2.898 years? 14) A sample of bone contains 3 mg of carbon-14. An equally massive bone of the same animal species would contain 96 mg of carbon-14 in a fresh carcass. How old is the bone sample assuming the half-life of carbon-14 is 5730 years. 15) Place the following three forms of radiation in order of their minimum shielding requirements (least to greatest). Alpha, beta, gamma. 16) List three uses of radioactive materials. 17) What is the difference between nuclear fission and nuclear fusion. 18) Explain why nuclear fission is used to generate power in power plants and nuclear fusion is not.