Using the Bohr model, estimate the wavelength ë of the Ká characteristic X-ray for a metal an atom of which contains Z = 50 protons.

Moseley's law

1/λ = R• (Z –σ)^2•(1/n^2 -1/m^2),
where
R=1.1•10^7 m^-1 is the Rydberg constant,
Z = 50,
σ = 1 for K-series,
for K-β: n = 1, m = 3.
So
1/λ = 1.1•10^7 • (50 –1)^2•(1 - 1/9) =…
λ = 4.26•10^-11 m