Question

Cu Kα radiation can ionize 1s electrons in which of the following elements?

(a) Cobalt

(b) Helium

(c) Nickel

(d) Hydrogen

The question was asked in class test.

I want to ask this question from Sources of Background Radiation Fluorescence topic in division X-Ray Diffraction of Solid State Chemistry

Answer 1

Right choice is (a) Cobalt

The explanation: Cu Kα radiation can ionize 1s electrons in cobalt and iron but not in nickel, helium and hydrogen. Because the ionization potentials of 1s electrons in nickel, cobalt and iron correspond to 1.4880, 1.6081 and 1.7433 A˚ and Cu Kα X-rays can ionize electrons in atoms whose ionization energy has a value corresponding to λ > 1.5418 A˚.