Explain why only two spectral lines are observed for Ka n2 t

Explain why only two spectral lines are observed for Ka (n=2 to n=1) x-rays.

Solution

Characteristic x-rays are emitted from heavy elements when their electrons make transitions between the lower atomic energy levels.

The characteristic x-ray emission occur when vacancies are produced in the n=1 or K-shell of the atom and electrons drop down from above to fill the gap. The x-rays produced by transitions from the n=2 to n=1 levels are called K-alpha x-rays, and those for the n=31 transition are called K-beta x-rays.

These are the two main emissions which occur and hence these two sharp spectral lines are observed.