To learn how to calculate the binding energy of a nucleus. The measured masses o

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To learn how to calculate the binding energy of a nucleus. The measured masses of nuclei are consistently lower than predicted by the sum of their particles. This discrepancy is called the mass defect, and it can be used to calculate the nuclear binding energy according to Einstein's famous equation E=mc2 where E is the energy produced, m is the mass lost, and c=3.00×108 m/s. Nuclear binding energy is the energy holding the nucleons together and is a measure of nuclear stability. The proton mass is 1.007276 amu , the neutron mass is 1.008665 amu , and the electron mass is 5.486×104 amu . Part A What is the expected mass of a fluorine-19 nucleus, based on the total mass of its protons and neutrons? Express your answer in atomic mass units using seven significant figures. 19.15213 amu SubmitHintsMy AnswersGive UpReview Part Correct Part B The actual measured mass of a fluorine-19 atom is 18.998403 amu . What is the mass defect, m, for a fluorine-19 nucleus? Express your answer in atomic mass units using six significant figures. m = .153731 amu SubmitHintsMy AnswersGive UpReview Part Incorrect; One attempt remaining; Try Again Part C What is the binding energy for a fluorine-19 nucleus? Express your answer numerically in joules per mole. E = 7.537 J/mol SubmitHintsMy AnswersGive UpReview Part Incorrect; Try Again; 3 attempts remaining Part D What is the binding energy, E, for a fluorine-19 nucleus in MeV/nucleon? Recall that 1 MeV=1.60×1013 J. Express your answer numerically in millions of electron volts per nucleon. E = 7.55780 MeV/nucleon SubmitHintsMy AnswersGive UpReview Part Incorrect; Try Again; 4 attempts remaining

Explanation / Answer

Part A What is the expected mass of a fluorine-19 nucleus, based on the total mass of its protons and neutrons?

Expected mass -> fluorine has 9 protons, and 19-9 = 10 neutrons

so

mass of protons = 1.007276 *9 = 9.065484

mass of neutrons = 1.008665 *10 = 10.08665

total mass = 10.08665+9.065484 = 19.152134 amu

Part B The actual measured mass of a fluorine-19 atom is 18.998403 amu . What is the mass defect, m, for a fluorine-19 nucleus?

Mass deffect = Actual Mass - Theoretical mass = 19.152134 - 18.998403 = 0.153731 amu

Part C What is the binding energy for a fluorine-19 nucleus? Express your answer numerically in joules per mole. E = 7.537 J/mol

Apply Einstein equation

E = m*c^2 =

mass= 0.153731 /(6.022*10^23) = 2.55282*10^-25 g/mol --> 2.55282*10^-28 kg/mol

E = m*c^2 = (2.55282*10^-28)(3*10^8)^2 = 2.2975*10^-11 J/mol

Part D What is the binding energy, E, for a fluorine-19 nucleus in MeV/nucleon?

Nucleon = neutron + protons = 9+10 = 19

E per nucleon = E / nucleon =( 2.2975*10^-11 )/( 19) = 1.20*10^-12 J/nucleon

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