The atomic mass of an element ₁₀X²⁰ is 19.98170 amu. The binding energy per nucleon of that element is: [given mass of neutron = 1.00867 amu and mass of proton = 1.00783 amu and 1amu = 931 MeV]

Step-by-step solution

Number of protons, Z = 10 Number of neutrons, A - Z = 20 - 10 = 10 Total mass of nucleons = 10 m_p + 10 m_n Total mass of nucleons = 10(1.00783) + 10(1.00867) = 10.0783 + 10.0867 = 20.1650 amu Mass defect, m = Mass of nucleons - Mass of nucleus m = 20.1650 - 19.98170 = 0.1833 amu Total binding energy, BE = m 931 MeV BE = 0.1833 931 = 170.6523 MeV Binding energy per nucleon = BE A = 170.6523 20 = 8.5326 MeV/nucleon 8.533 MeV/nucleon Answer: 8.533 MeV / nucleon