The first ionization energy of a hydrogen atom is 2.18 aj (attojoules). what is the frequency and wavelength, in nanometers, of photons capable of just ionizing hydrogen atoms? values for constants can be found here.

1) Frequency:

the energy of the photon absorbed must be equal to the ionization enegy of the atom, which is

The energy of a photon is given by

where is the Planck's constant. By using the energy written above and by re-arranging thsi formula, we can calculate the frequency of the photon:

2) Wavelength: 91.2 nm

The wavelength of the photon can be found from its frequency, by using the following relationship:

where is the speed of light and f is the frequency. Substituting the frequency, we find

explanation:

newton's third law, for every action there is an equal and opposite reaction.