Calculate the wavelength of radiation emitted when an electron in a hydrogen atom jumps from n = ∞ to n = 1.

The energy of the nth level for any atom is determined by the radius and quantum number by:
En = −Z²k²e⁴me²/2n²
For hydrogen atom the energy varies with shell number as:
En = −13.6/n² eV
Energy released from the jump of an electron from n = ∞ to n = 1 is:
E = −13.6(1/∞² − (1/1²)) eV = 13.6 eV
A photon of this energy is given by,
E = hc/λ ⇒ λ = hc/E = 91.17 nm