Question

Calculate the wavelength and frequency of light emitted when an electron changes from n=5 to n=2 in the H atom.

Wavelength = ???m

Frequency = ??? s^-1

Answer 1

Here photon will be emitted

1/wavelength = R* (1/nf^2 - 1/ni^2)

R is Rydberg constant. R = 1.097*10^7

1/wavelength = R* (1/nf^2 - 1/ni^2)

1/wavelength = 1.097*10^7* (1/2^2 - 1/5^2)

wavelength = 4.341*10^-7 m

wavelength = 434 nm

we have:

wavelength = 4.341*10^-7 m

we have below equation to be used:

frequency = speed of light/wavelength

=(3.0*10^8 m/s)/(4.341*10^-7 m)

= 6.911*10^14 Hz

wavelength = 4.341*10^-7 m

frequency = 6.911*10^14 s-1