Question

Find the largest and shorted wavelengths in the Lyman
series for hydrogen. In what region of the electromagnetic spectrum does each
series lie?

Answer 1

Correct Answer - A::B
The transition equation for Lyman series is given by`
(1)/(lambda) = R ((1)/(1^2) - (1)/(n^2)) , n = 2,3….`
The largest wavelength is correspondign to n= 2`
`:. (1)/(lambda_(max)) = 1.097xx10^7((1)/(1)-(1)/(4)), = 0.823xx10^7`
`:. lambda_(max) = 1.2154xx10^(-7) m = 1215Å`
The shortest wavelength corresponds to `n = oo` :. (1)/(lambda_(min) = 1.097xx10^7 ((1)/(1) - (1)/(00))`
or lambda_(min) = 0.911xx10^(-7) m = 911Å`
. Both of these wavelengths lie in ultraviolet (UV) region of electromagnetic spectrum.