2.55 Emission transitions in the Paschen series end at orbit n = 3 and start from orbit n and can be represented as
Calculate the value of n if the transition is observed at 1285 nm. Find the region of the spectrum.
Given transition in the Paschen series end at orbit and starts from orbit n: .........................(1)
.........................(2)
Equating both (1) and (2) equations: we get
Therefore, the radiation corresponding to 1285 nm lies in the infrared region.