Same chapter3 marksDifficulty: Medium
Define mass defect and binding energy, and explain why the binding energy per nucleon curve peaks near iron.
Atoms and Nuclei
3 marksDifficulty: Medium
State two limitations of Bohr's model of the atom.
Original Khojo Papers practice question — not from a past board paper.
Answer
It applies only to hydrogen and to hydrogen-like ions with one electron, and fails for atoms with more electrons. It cannot explain the fine structure of spectral lines, the relative intensities of the lines, or the splitting of lines in a magnetic or an electric field, and it arbitrarily mixes classical and quantum ideas.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The wave-mechanical model replaced fixed orbits with orbitals of probability.
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