UPSC Combined Geo-Scientist, Mains · 2024 · Mains Paper II
Q14(b). Energies of the two levels for a 0.5 nm box
Question
Calculate the corresponding energies (in J) if the side length of the box is 0.5 nm.
Answer in brief
E(2, 2, 2) = 2.892 × 10⁻¹⁸ J (18.05 eV); E(1, 2, 3) = 3.374 × 10⁻¹⁸ J (21.06 eV).
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Coversparticle in a box energyquantum confinementh²/8mL²electron energy levelsbox length
All parts of Question 14
- 14(a) Non-degenerate and six-fold levels in a cubic box5 marks
- 14(b) Energies of the two levels for a 0.5 nm box5 marks
- 14(c) Wavelength of the (2,2,2)–(1,2,3) transition5 marks
- 14(d) Quantum efficiency in the uranyl oxalate actinometer5 marks