What is Emission: Definition and 566 Discussions

The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an atom or molecule making a transition from a high energy state to a lower energy state. The photon energy of the emitted photon is equal to the energy difference between the two states. There are many possible electron transitions for each atom, and each transition has a specific energy difference. This collection of different transitions, leading to different radiated wavelengths, make up an emission spectrum. Each element's emission spectrum is unique. Therefore, spectroscopy can be used to identify elements in matter of unknown composition. Similarly, the emission spectra of molecules can be used in chemical analysis of substances.

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  1. A

    Atmospheric Emission: Climate Change, CO2 & Quantum Chemistry

    A friend is a quantum chemist. He is in agreement that climate change is bad (he feels the primary problems with CO2 is ocean acidification). Anyway he states there is no credible research showing that atmospheric CO2 re-emits radiation to the planet. His belief is that the intersection of IR...
  2. F

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    Dear Forum, An object, like a metal, that is highly reflecting (white body) is very different from a very emissive object (black body). An object that closely behaves like a black body absorbs all the incident radiation. But it also "emit" all the absorbed radiation (over a range of...
  3. MTd2

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  4. A

    Isotropic absorption and emission

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  5. C

    Effects of frequency on rate of emission of photoelectrons

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  6. Entanglement

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  7. N

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  8. LotusTK

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  9. L

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  10. M

    About radioactive emission by Jupiter

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  11. J

    If a photon's emission is detected is it real or virtual?

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  12. F

    Does the Drude model predict the emission of em waves?

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  13. A

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  14. dheeraj

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  15. N

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  16. PeteyCoco

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  17. G

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  18. R

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  19. T

    Airborne particle focusing in heated chamber using thermal emission?

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  20. U

    Emission from hydrogen discharge tube

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  21. C

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  22. H

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  23. P

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  24. M

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  25. S

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  26. N

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  27. ajayguhan

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  28. StevieTNZ

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  29. Q

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  30. G

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  31. D

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  32. T

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  33. I

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  34. S

    Find the calorific value of fuel, given emission data

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  35. snoopies622

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  36. G

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  37. U

    Orbit about star, emission spectrum of light

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  38. U

    What ion is this? even emission lines matches lyman series of hydrogen

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  39. G

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  40. R

    Photon emission by an excited hydrogen atom

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  41. K

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  42. jaumzaum

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  43. Q

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  44. O

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  45. S

    How Many Hydrogen Atoms Minimum for All Emission Spectra from n=5?

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  46. B

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  47. trollcast

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  48. K

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  49. E

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  50. M

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