The lines occurring in an emission spectrum are all electromagnetic waves, which means that their speed in a vacuum is
3 x 10⁸ m/s
We can use the equation,
v = fλ
which relates the velocity of a wave to the frequency and wavelength. Substituting values,
3 x 10⁸ = f * 434 x 10⁻⁹
f = 6.91 x 10¹⁴ Hz
The frequency of the wave will be 6.91 x 10¹⁴ oscillations per second.
