Answer
The energy difference between the two states of the iron atom that give rise to this transition is $~~6.44~keV$
Work Step by Step
We can find the energy associated with a wavelength $\lambda = 193~pm$:
$E = \frac{hc}{\lambda}$
$E = \frac{(6.626\times 10^{-34}~J\cdot s)(3.0\times 10^8~m/s)}{193\times 10^{-12}~m}$
$E = 1.03 \times 10^{-15}~J$
$E = (1.03 \times 10^{-15}~J)(\frac{1~eV}{1.6\times 10^{-19}~J})$
$E = 6.44\times 10^3~eV$
$E = 6.44~keV$
The energy difference between the two states of the iron atom that give rise to this transition is $~~6.44~keV$
