In which process is some of the photon's energy used to dislodge an orbital electron and the remainder of the energy given to the free electron as kinetic energy?

The correct choice is the process known as the photoelectric effect. In the photoelectric effect, when a photon encounters an atom, it can transfer its energy to one of the orbital electrons within that atom. If the photon's energy is sufficient, it can completely overcome the binding energy that holds the electron in its orbital shell, thus ejecting the electron from the atom.

The energy of the incident photon is not entirely lost in the process; rather, the energy used to dislodge the orbital electron is equal to the binding energy of that electron. The excess energy, after accounting for the binding energy, is converted into kinetic energy of the now-free electron. This results in the ejected electron having a particular kinetic energy, which can be calculated by subtracting the electron’s binding energy from the initial energy of the incident photon.

This fundamental mechanism underlies many applications in radiography and radiation safety, as understanding how photons interact with matter is crucial for assessing radiation exposure and its biological effects.

In contrast, Compton scatter is a different process in which a photon collides with a loosely bound outer electron, resulting in a change in the direction of the photon and some energy being transferred to the electron. Pair production involves a photon interacting with a