The first ionization energy of a carbon atom is 1.81 aJ. What is the frequency and wavelength, in nanometers, of photons capable of just ionizing carbon atoms?

v=______s^(-1)

lambda =_____nm

Assuming an ionization efficiency of 47.0%, how many such photons are needed to ionize 1.00 × 1016 atoms?

=_______protons

1 answer

What's 1.81 aJ? Do you mean kJ so IP = 1810 J.
Then 1810 = hc/wavelength. Solve for wavelength in meters and convert to nm.
c = freq x wavelength will let you solve for freq.

1810 J/atom x 1E16 atoms x 0.47 = ?