The wavelength of the line for an element of atomic number 57 is . What is the wavelength of line fo — Atomic Structure Chemistry Question

💡 Solution & Explanation

By Moseley's law, $\lambda \propto \frac{1}{(Z-1)^2}$. Ratio $\frac{\lambda_{29}}{\lambda_{57}} = \frac{(57-1)^2}{(29-1)^2} = \frac{56^2}{28^2} = 2^2 = 4$. So $\lambda_{29} = 4\lambda$. Therefore, correct answer is C.