Question

Explain why characteristic x rays are the most energetic in the EM emission spectrum of a given element.

a) They result from transitions involving higher atomic energy levels.

b) They have shorter wavelengths than other x rays.

c) They are emitted during nuclear reactions.

d) They are emitted at higher temperatures.

Answer 1

Characteristic x-rays are the most energetic due to transitions of inner-shell electrons to fill lower energy level vacancies, leading to emissions that are unique for each element.

Step-by-step explanation:

Characteristic x-rays are the most energetic in the electromagnetic (EM) emission spectrum of a given element because they result from transitions involving inner-shell electrons. When an inner-shell vacancy is filled by an electron from a higher energy level, the atom emits a characteristic x-ray with high energy. For instance, when an electron from the n = 2 level fills a vacancy in the n = 1 level, a Kα x-ray is emitted, and even more energetic Kβ x-rays occur when an electron from an n = 3 level transitions to the n = 1 level. These emissions depend on the energy levels of the electrons within the atom and are therefore unique to each element, allowing for element identification through their x-ray spectra.