In two-photon ionization spectroscopy, the combined energy of two different photons is used to remove an electron from an atom or molecule. In such an experiment, a potassium atom in the gas phase is ionized by two different lasers, one of which has a wavelength of 770.0 nm. What is the maximum wavelength for the second laser that will cause two-photon ionization? The ionization energy of potassium is 6.96E-19 J. nm

Respuesta :

Answer:

The maximum wavelength of second laser is 453.8 nm

Explanation:

Given:

Wavelength of light [tex]\lambda = 770 \times 10^{-9}[/tex] m

Ionization energy of potassium [tex]= 6.96 \times 10^{-19}[/tex] J

First find the energy related to the one of light,

    [tex]E = \frac{hc}{\lambda}[/tex]

Where [tex]h = 6.626 \times 10^{-34}[/tex], [tex]c = 3 \times 10^{8} \frac{m}{s}[/tex]

    [tex]E = \frac{6.626 \times 10^{-34} \times 3 \times 10^{8} }{770 \times 10^{-9} }[/tex]

    [tex]E = 2.58 \times 10^{-19}[/tex]J

This is the energy of the first laser, the missing energy is given by.

   [tex]E' = (6.96 - 2.58) \times 10^{-19}[/tex]

   [tex]E ' = 4.38 \times 10^{-19}[/tex]J

For finding wavelength of second laser,

   [tex]E' = \frac{hc}{\lambda '}[/tex]

    [tex]\lambda ' = \frac{hc}{E'}[/tex]

    [tex]\lambda ' = \frac{6.626 \times 10^{-34} \times 3 \times 10^{8} }{4.38 \times 10^{-19} }[/tex]

    [tex]\lambda ' = 453.8 \times 10^{-9 }[/tex] m

    [tex]\lambda ' = 453.8[/tex] nm

Therefore, the maximum wavelength of second laser is 453.8 nm