How does the energy needed to move an electron to a higher energy level?

An electron will jump to a higher energy level when excited by an external energy gain such as a large heat increase or the presence of an electrical field, or collision with another electron.

What happens when an electron goes to a higher energy level?

The electrons in an atom exist in various energy levels. When an electron moves from a lower energy level to a higher energy level, energy is absorbed by the atom. When an electron moves from a higher to a lower energy level, energy is released (often as light).

Can electrons excite other electrons?

Electrons can also be excited by electrical excitation, where the original electron absorbs the energy of another, energetic electron. When an excited electron falls back to a lower energy state again, it is called electron relaxation.

Why does a photon need an exact amount of energy to excite an electron?

An electron can only be excited to another level if it absorbs the exact amount of energy as the difference between the two levels. Therefore the energy of the photon it absorbs needs to be of a specific energy to excite it and, as E = hf, its energy needs to be a specific frequency.

Why does electron affinity increase with nuclear charge?

As atomic number increases, more protons are added to the nucleus. More number of protons in the nucleus will mean more positive charge to attract the electrons, and hence, as nuclear charge increases, electron affinity increases.

Why don’t electrons emit photons when they move?

At rest, and cold an electron doesn’t emit photons because it isn’t absorbing energy and changing its energy state. For an electron to move something has to hit it. The source of light when changing direction is related to the emf electrons carry.

What happens when a photon is absorbed by a metal?

When a photon is absorbed in a metal by this field, it creates the photoelectric effect. Then there is enough energy to get electrons free of the atom and an electrical current flows. Another reaction that electrons experience is when they absorb any energy.

How does the photoelectric effect work?

The photoelectric effect is the result. of collisions between photons and electrons that knock the electrons out of the metal. ! = work function: amount of energy binding the electron to the metal. Recall that E=hf gives the energy of the photon.

What are the characteristics of photons?

• Photons travel some considerable distance before undergoing a more. “catastrophic” interaction leading to partial or total transfer of the photon energy to electron energy. • These electrons will ultimately deposit their energy in the medium. • Photons are far more penetrating than charged particles of similar energy.