Question

Calculate the wavelength (in nm) of the red line in the visible spectrum of excited H atoms using Bohr Theory.

(Question #2)

QUESTIONS 1. Determine the energy change (in Joules) associated with the transition from n = 2 to n 4 in the Hydrogen atom. AE 2.18 x 10 J nf - tests AE2.1io o.as-o.o6d5) x IDJ -/4 2. Calculate the wavelength (in nm) of the red line in the visible spectrum of excited H atoms using Bohr Theory.

Answer 1

H- atom visible spectrum means it is Balmer series.   in balmer series n1 = 2 . it is fixed value .

we know that visible region order : V I B G Y O R . among these red color is highest wavelength and lowest energy

so 3 --------> 2 lowest energy

     4 -----------> 2 higher enyergy

     5 -----------> 2 next higher energy

     6 ------------> 2 next higher and so on......

so that for red color another n value must be higher wave length that is n = 3

now you everything

n1 = 2 . n2 = 3

energy = 2.18 x 10^-18 [1 / n1^2 - 1/ n2^2 ]

             = 2.18 x 10^-18 [ 1/ 2^2 - 1/ 3^2 ]

            = 3.03 x 10^-19 J

energy = h c / wave length

3.03 x 10^-19 = (6.625 x 10^-34 ) (3 x 10^6) / wave length

wave length = 6.61 x 10^-7 m

                      = 661 x 10^-9 m

                       = 661 nm

wave length = 661 nm