Answer :

The wavelength of a line in the spectrum of hydrogen is 6564A° .

Let us consider balmer series for calculating wavelength of a line in the spectrum of hydrogen.

From line spectrum of hydrogen , we know that,

[tex]wave \: number \: = R( \frac{1}{ {n1}^{2} } - \frac{1}{ {n2}^{2} } )[/tex]

where n1 is the lower energy level of balmer series.

n2 is the higher energy level of balmer series.

n1 = 2 , n2 = 3 for balmer series.

R is the Rydberg's constant = 109677 cm^-1

Wave number = 109677 ( 1/2^2 - 1/3^2 ) cm^-1

= 109677 ( 1/4 - 1/9 ) cm^-1

= 109677 ( 5/36 ) cm^-1

= 15232.91 cm^-1

As we know,

wavelength is the reciprocal of wave number.

Thus, wavelength = 1/wave number = (1 /15232.91) cm

wavelength = 6.564733 cm = 6564 A°

Thus, the wavelength of a line in the spectrum of hydrogen is 6564A° .

Hydrogen spectrum is observed by examining the light emitted when a discharged passes through a tube containing hydrogen. the tube contains millions and trillions of atoms in varying states of excitation. these atoms undergo transition from a higher orbit to lower one in a random fashion, thus giving rise to a number of lines.

Wavelength and wave number depends upon the orders of the two orbits between which the transition takes place.

Learn more about wavelength here :

brainly.com/question/10750459

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