Bohr Model and Discrete Atomic Energy Levels

Bohr proposed that an electron in hydrogen can occupy certain stationary states. In the historical Bohr model: **mvr = nħ** where: `n=1,2,3,...`

The allowed energy levels are: **Eₙ = −13.6eV/n² For: `n=1` E₁=−13.6eV This is the ground state. As `n` increases: energy becomes less negative. At: `n→∞` E→0** corresponding to the ionization limit.

When an electron changes energy level: **ΔE = E_f−E_i A photon is emitted or absorbed with: |ΔE|=hf** Emission: electron moves to lower energy. Absorption: electron moves to higher energy.

**Eₙ=−13.6eV/n² |ΔE|=hf=hc/λ**