The Kα X-ray emission line of tungsten occurs at λ = 0.021 nm. The energy difference between K and L levels in this atom is about
Answer & explanation
Correct answer: option 3
$\text{Energy difference betweel K and L level is given by } \lambda_{K_{\alpha}} = \frac{hc}{E_K - E_L}$
$E_K - E_L = \frac{1240 eV}{0.021} = 59KeV$