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Outline:
 1.Define mass defect. A) an atom with too many neutrons B) energy absorbed in a radioactive reaction C) energy released in a radioactive reaction D) the difference in mass between an atom and the sum of its separate components E) the difference in mass between a radioactive atom and a nonradioactive atom Answer: D
演講者: 洪國明
觀看 (640), 討論 (0)
演講日期: 2015-07-03
上架時間: 2015-07-05
上傳者: energy4104
01:27
Outline:
 1.2) Describe what changes occur during alpha decay. The mass number and atomic number increases. B) The mass number and atomic number decreases. C) The mass number increases and the atomic number decreases. D) The mass number and atomic number do not change. E) The mass number is unchanged and the atomic number increases. Answer: B
演講者: 洪國明
觀看 (454), 討論 (0)
演講日期: 2015-07-03
上架時間: 2015-07-05
上傳者: energy4104
00:38
Outline:
 1.3) Which particle has the lowest penetrating power? neutron particle B) alpha particle C) gamma particle D) electron emission E) positron capture Answer: B
演講者: 洪國明
觀看 (471), 討論 (0)
演講日期: 2015-07-03
上架時間: 2015-07-05
上傳者: energy4104
01:06
Outline:
 1.4) The combination of two light nuclei to form a heavier nuclei is called ________. nuclear fission B) nuclear fusion C) half life D) radioactive cleavage E) radioactive merge Answer: B
演講者: 洪國明
觀看 (529), 討論 (0)
演講日期: 2015-07-03
上架時間: 2015-07-05
上傳者: energy4104
00:22
Outline:
 1.5) The chart below shows the mass of a decaying nuclide versus time. What is the half-life of the decay?70 min B) 25 min C) 35 min D) 15 min Answer: C
演講者: 洪國明
觀看 (452), 討論 (0)
演講日期: 2015-07-03
上架時間: 2015-07-05
上傳者: energy4104
01:01
Outline:
 1.6) Iron-59 is a beta emitter with a half-life of 44.5 days. If a sample initially contains 132 mg of iron-59, how much iron-59 is left in the sample after 265 days?A) 33.2 mg B) 0.00 mg C) 2.13 mg D) 66.0 mgAnswer: C
演講者: 洪國明
觀看 (486), 討論 (0)
演講日期: 2015-07-03
上架時間: 2015-07-05
上傳者: energy4104
01:09
Outline:
 1.7) An artifact has a carbon-14 decay rate of 8.55 disintegrations per minute per gram of carbon (8.55 dis/min ·g C). Living organisms have carbon-14 decay rate of 15.3 dis/min · g C. How old is the artifact? (The half-life of carbon-14 is 5730 yr.)1.21 × 10-4 yr B) 3.20 × 103 yr C) 4.81 ×103 yr D) 2.10 × 103 yrAnswer: C
演講者: 洪國明
觀看 (580), 討論 (0)
演講日期: 2015-07-03
上架時間: 2015-07-05
上傳者: energy4104
01:14
Outline:
 1.8) An igneous rock contains a Pb-206/U-238 mass ratio of 0.372. How old is the rock? (U-238 decays into Pb-206 with a half-life of 4.5 × 109 yr.)2.05 × 109 yr B) 4.50 × 109 yr C) 2.32 × 109 yr D) 6.42 × 109 yrAnswer: C
演講者: 洪國明
觀看 (640), 討論 (0)
演講日期: 2015-07-03
上架時間: 2015-07-05
上傳者: energy4104
02:23
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