Part1of2100points how much energy is required to

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015(part1of2)10.0pointsHow much energy is required to cause an elec-tron in hydrogen to move from then= 1 stateto then= 4 state?7 K.Correct answer: 12.75 eV.
7 K.Explanation:
01710.0points
douglas (jed3339) – Homework 10 – yao – (54790)701810.0pointsWhat is the energy released in the alpha decayof23892U? The mass of21080Hg21481Tl5.21483BicorrectExplanation:The beta decay will increase the protonnumber by 1 (with the negatively chargedbeta particle, or electron, keeping the totalcharge of the final decay products the sameas the charge of the initial nucleus), whilethe total number of protons and neutrons re-mains unchanged. (Gamma rays, being highenergy photons, carry neither electric chargenor nucleon number).Thus the resulting nucleus is21483Bi.02010.0pointsA radioactive isotope is found to decay toone-sixteenth its original amount in 12 years.What is the half-life of this isotope?Correct answer: 3 y.Explanation:The decay pattern is12,14,18,116, whichmeans 4 half lives:12 y = 4 (3 y)andτhalf= 3 y.02110.0pointsA piece of charcoal used for cooking is foundat the remains of an ancient campsite.A1 kg sample of carbon from the wood has anactivity of 2180 decays per minute.Find the age of the charcoal. Living mate-rial has an activity of 15 decays/minute pergram of carbon present and the half-life of14Cis 5730 y.01910.0pointsA negative beta particle and a gamma rayare emitted during the radioactive decay of anucleus of21482Pb. [An antineutrino, ¯νe,wouldalso be emitted, but would not be detected.]What will be the resulting nucleus?3.21080Hg4.21481Tl5.21483BicorrectExplanation:The beta decay will increase the protonnumber by 1 (with the negatively chargedbeta particle, or electron, keeping the totalcharge of the final decay products the sameas the charge of the initial nucleus), whilethe total number of protons and neutrons re-mains unchanged. (Gamma rays, being highenergy photons, carry neither electric chargenor nucleon number).Thus the resulting nucleus is21483Bi.02010.0pointsA radioactive isotope is found to decay toone-sixteenth its original amount in 12 years.What is the half-life of this isotope?Correct answer: 3 y.Explanation:The decay pattern is12,14,18,116, whichmeans 4 half lives:12 y = 4 (3 y)andτhalf= 3 y.02110.0pointsA piece of charcoal used for cooking is foundat the remains of an ancient campsite.A1 kg sample of carbon from the wood has anactivity of 2180 decays per minute.Find the age of the charcoal. Living mate-rial has an activity of 15 decays/minute pergram of carbon present and the half-life of14Cis 5730 y.

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