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Heat treatment of muscular pain involves radiation of wavelength of about 900 nm . Which spectral line of H-atom is suitable for this purpose ?

\left [ R_{H}= 1\times 10^{5}cm^{-1},h= 6.6\times 10^{-34}Js,c= 3\times 10^{8}ms^{-1} \right ]

  • Option 1)

    Paschen , 5\rightarrow 3

     

  • Option 2)

    Lyman,\: \: \infty \rightarrow 1

  • Option 3)

    \; \; \; Balmer,\: \: \infty \rightarrow 2\: \:

     

  • Option 4)

    Paschen,\: \: \infty \rightarrow 3

Answers (1)

best_answer

 

Paschen , Bracket and Pfund Series spectrums -

Infrared Region

-

 

 

Line Spectrum of Hydrogen like atoms -

\frac{1}{\lambda }= RZ^{2}\left ( \frac{1}{n_{1}^{2}}-\frac{1}{n_{2}^{2}} \right )

 

- wherein

Where R is called Rhydberg constant, R = 1.097 X 107 , Z is atomic number

n1= 1,2 ,3….

n2= n1+1, n1+2 ……

 

 

Balmer Series Spectrum -

\frac{1}{\lambda }= RZ^{2}\left ( \frac{1}{n_{1}^{2}}-\frac{1}{n_{2}^{2}} \right )

Where n_{1}=2\ and\ n_{2}=3, 4, 5, 6 .....

It lies in visible region

As we know that

Paschen, \infty \rightarrow3 -is correct

\frac{1}{\lambda }=R \left ( \frac{1}{n_{1}^{2}} -\frac{1}{n_{2}^{2}}\right )= 10^{7}\left ( \frac{1}{\left ( 3 \right )2} -\frac{1}{\infty }\right )

\lambda = 9\times 10^{-7}m

\lambda = 900nm.

 

 


Option 1)

Paschen , 5\rightarrow 3

 

Option 2)

Lyman,\: \: \infty \rightarrow 1

Option 3)

\; \; \; Balmer,\: \: \infty \rightarrow 2\: \:

 

Option 4)

Paschen,\: \: \infty \rightarrow 3

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