Why is light emitted

Every element has a different number of electrons and a different set of energy levels. Thus, each element emits its own set of colours. See, for example, mercury and neon above. Those colours are as distinctive to each element as fingerprints are to people. Why do elements emit colors when heated? Ernest Z. Apr 10, Explanation: Heating an atom excites its electrons and they jump to higher energy levels. Part of the Oxford Instruments Group Expand.

Oxford Instruments. Investors Careers. Life Science Cameras. Control Software. Physical Science Cameras. OEM Portfolio. Support Service and Support. Learning Centre Asset. What is Light Emission Light can be produced by matter which is in an excited state and, as we will show, excitation can come from a variety of sources.

Black body radiation A body at a given temperature also emits a characteristic spectrum of light called black body radiation. Name Excitation source Examples of use Chemiluminescence Chemical reactions Emergency lighting Cathodeluminescence Electron beam Electron beam Sonoluminescence Sound energy Possible chemical reactions Triboluminescence Friction energy Gives rise to light emission seen when opening gum labels in the dark.

Absorption occurs when electrons absorb photons which causes them to gain energy and jump to higher energy levels. Notice emission in the picture above.

It shows the electron moving down energy levels. The color of the light emitted would result from the amount of energy as it moves through shells. Absorption is shown by the energy levels increasing as the photon gains energy.

The wavelengths shown relate to the amount of energy in the photon. Notice how the emitted light wavelengths are shorter than the absorbed light wavelengths. This would indicate that the emitted light has more energy in the photon than the absorbed light. This is important because it shows the shells that electrons move to when light is absorbed or emitted. The energy difference between orbitals can be calculated by measuring the frequency of radiation. Absorption and emission of light can reveal a lot about the structure of an atom.

Absorbed light is light that isn't seen while emitted light is light that is seen. Emission is when electrons return to energy levels. Absorption is when electrons gain energy and jump to higher energy levels. Absorption and emission of light reveals details about the atomic structure of an atom by telling us the amount of energy levels and the space between the energy levels. Here is a great YouTube video explaining and showing the excitement of electrons, emission, and absorption.