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Numericals on Wave number and Radius

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Q1. Calculate the wave number and wavelength of Balmer series of hydrogen spectrum in which electron jumps from orbit 3 to orbit 2.

Solution

Calculation of Wave Number

Here;

RH = 1.0968553 x 107 m-1

n1 = 2

n2 = 3

Z  = 1





Calculation of Wave Length 







Q2. What is the wavelength and wave number of radiation that is emitted when a hydrogen atom undergoes a transition from orbit 3 to orbit 1.

Solution

Calculation of Wave Number 

RH = 1.0968553 x 107 m-1

n1 = 1

n2 = 3















Q3.   Calculate the ratio of radius of second and third orbit of hydrogen atom. (Bohr’s radius =  0.529ºA)

Solution 












Q4. If the radius of first Bohr orbit is ‘x’ then calculate 
the radius of the third orbit of hydrogen.

Solution 



Q1.Calculate the energy of the electron in the                        ground state and first excited state of the                      hydrogen atom

Solution

Part (A)

Z for H = 1

n for ground state = 1














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