Bohr's model

 The Bohr model is a historical model of the atom proposed by Niels Bohr in 1913. It was a major advancement in understanding atomic structure, especially for hydrogen-like atoms. Here's a simple breakdown of the Bohr model:

🔬 Key Features of the Bohr Model

  1. Electrons orbit the nucleus in fixed circular paths called energy levels or shells.

  2. Each orbit has a specific energy associated with it, and electrons in the same orbit have the same energy.

  3. Electrons can jump between energy levels:

    • When they absorb energy, they move to a higher level (excited state).

    • When they release energy (usually as light), they fall to a lower level (ground state).

  4. The energy difference between the levels corresponds to the frequency of light emitted or absorbed:

    E=hνE = h \nu

    where EE is energy, hh is Planck’s constant, and ν\nu is frequency.

🧪 Example: Hydrogen Atom

  • The simplest Bohr atom is hydrogen (1 proton, 1 electron).

  • Its electron orbits at specific distances (quantized radii).

  • The lowest energy level (n=1) is called the ground state.

  • Higher levels (n=2, 3, 4...) are excited states.

🌟 Bohr's Successes

✅ Explained the spectral lines of hydrogen
✅ Introduced quantization of electron energy levels
✅ Laid groundwork for quantum mechanics

⚠️ Limitations

❌ Only works well for hydrogen-like atoms (1 electron)
❌ Doesn’t explain atoms with multiple electrons
❌ Doesn’t incorporate electron wave behavior (fixed later by quantum mechanics)

Would you like a diagram of the Bohr model for hydrogen or a different atom?




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