Calculate the frequency and the wavelength of the radiation in nannometers emmitted when an electron in the hydrogen atom jumps from 3rd orbit to the ground state. In which region of the electromagnetic spectrum will this line lie.

Frequency = R ( 1/ n1^2 - 1/ n2 ^2)

Here R is Rydberg Constant = 1.09766 * 10^ 7 m ^-1

n1 = 1 and n2 = 3. We put the values in formula and we get the frequency = 9.75 *10 ^ 6 m^-1

and wavelength = 1/ frequency = 1.02 * 10 ^ -7 meter. The Spectrum will lie in Layman series.