Statement (i): The mass energy of a nucleus is actually smaller than the sum of the mass energies of individual protons and neutrons due to the binding energy. Therefore, this statement is false.
Statement (ii): When a nucleus is separated into its nucleons, energy equal to the binding energy must be supplied to overcome the nuclear forces holding the nucleons together. This statement is true.
Statement (iii): The binding energy is indeed a measure of how strongly the nucleons (protons and neutrons) are held together within the nucleus. This statement is true.
Statement (iv): Nuclear fission involves the splitting of a heavy nucleus into lighter nuclei, which results in a release of binding energy, leading to a higher binding energy per nucleon in the fragments. This statement is true.
Thus, the correct answer is that statements (ii), (iii), and (iv) are true.
Let's evaluate the truthfulness of the given statements regarding nuclear binding energy:
False. The mass of a nucleus is less than the sum of the masses of its individual nucleons. This mass defect is converted into binding energy ($BE = \Delta m c^2$), meaning the mass energy of the nucleus is actually smaller.
True. The binding energy represents the energy holding the nucleons together. To separate them, an equivalent amount of energy must be supplied to overcome the nuclear forces.
True. A higher binding energy per nucleon indicates a stronger attraction between the nucleons and a more stable nucleus.
True. In nuclear fission, a heavy nucleus splits into lighter nuclei that have a higher binding energy per nucleon, releasing a significant amount of energy in the process as the system moves towards a more stable state.
Based on the evaluation, statements (ii), (iii), and (iv) are true.
Answer: (2) Statements (ii), (iii) and (iv) are true
Mass Defect and Energy Released in the Fission of \( ^{235}_{92}\text{U} \)
When a neutron collides with \( ^{235}_{92}\text{U} \), the nucleus gives \( ^{140}_{54}\text{Xe} \) and \( ^{94}_{38}\text{Sr} \) as fission products, and two neutrons are ejected. Calculate the mass defect and the energy released (in MeV) in the process.
Given: