Energy-level diagram of hydrogen (with Lyman, Balmer, Paschen jumps)हाइड्रोजन का ऊर्जा स्तर आरेख (लाइमन, बामर, पाशन संक्रमणों सहित)Energy-level diagram of hydrogen (with Lyman, Balmer, Paschen jumps)
NCERT Fig 12.7 · Class 12 Physics · Chapter 12 · interactive diagram
Parts and what they mean
- n = 1, ground state: −13.6 eV (n = 1, निम्नतम अवस्था: −13.6 eV) — Lowest energy, smallest orbit (Bohr radius). At room temperature most H atoms are here.
- n = 2, first excited state: −3.40 eV (n = 2, प्रथम उत्तेजित अवस्था: −3.40 eV) — Needs 10.2 eV from the ground state to reach.
- n = 3, second excited state: −1.51 eV (n = 3, द्वितीय उत्तेजित अवस्था: −1.51 eV) — Needs 12.09 eV from the ground state.
- n = 4: −0.85 eV (n = 4: −0.85 eV) — Levels come closer and closer as n increases.
- n = 5: −0.54 eV (n = 5: −0.54 eV) — E₅ = −13.6/25 = −0.544 eV.
- n = 6: −0.38 eV (n = 6: −0.38 eV) — E₆ = −13.6/36 = −0.378 eV.
- n = ∞: 0 eV (n = ∞: 0 eV) — Electron completely removed (r = ∞) and at rest. Above 0 eV it is free and can have any energy (continuum).
- Continuum of free states (मुक्त अवस्थाओं का सांतत्यक) — Any energy above 0 eV is allowed for a free electron.
- Lyman series (to n = 1) (लाइमन श्रेणी (n = 1 पर)) — Jumps ending on n = 1: ultraviolet, 121.6 nm (2→1) down to the limit 91.2 nm.
- Balmer series (to n = 2) (बामर श्रेणी (n = 2 पर)) — Jumps ending on n = 2: visible lines 656.3, 486.1, 434.1, 410.2 nm …, limit 364.6 nm.
- Paschen series (to n = 3) (पाशन श्रेणी (n = 3 पर)) — Jumps ending on n = 3: infrared, 1875 nm (4→3) down to 820.4 nm.
- Ionisation energy 13.6 eV (आयनन ऊर्जा 13.6 eV) — Minimum energy to free the electron from the ground state. Bohr’s value matches experiment.
Original diagram drawn by Simple Learning Hub, based on NCERT Fig 12.7. Report a mistake