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Electromagnetic radiation ultraviolet

The dissociation energy of a carbon bromine bond is typically about 210 kJ/moL (a) What is the maximum wavelength of photons that can cause C—Br bond dissociation (b) Which kind of electromagnetic radiation— ultraviolet, visible, or infrared—does the wavelength you calculated in part (a) correspond to ... [Pg.778]

Which type of electromagnetic radiation, ultraviolet light, microwaves, or X-rays has the longest wavelengths ... [Pg.138]

Colorimetry, in which a sample absorbs visible light, is one example of a spectroscopic method of analysis. At the end of the nineteenth century, spectroscopy was limited to the absorption, emission, and scattering of visible, ultraviolet, and infrared electromagnetic radiation. During the twentieth century, spectroscopy has been extended to include other forms of electromagnetic radiation (photon spectroscopy), such as X-rays, microwaves, and radio waves, as well as energetic particles (particle spectroscopy), such as electrons and ions. ... [Pg.368]

The focus of this chapter is photon spectroscopy, using ultraviolet, visible, and infrared radiation. Because these techniques use a common set of optical devices for dispersing and focusing the radiation, they often are identified as optical spectroscopies. For convenience we will usually use the simpler term spectroscopy in place of photon spectroscopy or optical spectroscopy however, it should be understood that we are considering only a limited part of a much broader area of analytical methods. Before we examine specific spectroscopic methods, however, we first review the properties of electromagnetic radiation. [Pg.369]

In absorption spectroscopy a beam of electromagnetic radiation passes through a sample. Much of the radiation is transmitted without a loss in intensity. At selected frequencies, however, the radiation s intensity is attenuated. This process of attenuation is called absorption. Two general requirements must be met if an analyte is to absorb electromagnetic radiation. The first requirement is that there must be a mechanism by which the radiation s electric field or magnetic field interacts with the analyte. For ultraviolet and visible radiation, this interaction involves the electronic energy of valence electrons. A chemical bond s vibrational energy is altered by the absorbance of infrared radiation. A more detailed treatment of this interaction, and its importance in deter-... [Pg.380]

As discussed earlier in Section lOC.l, ultraviolet, visible and infrared absorption bands result from the absorption of electromagnetic radiation by specific valence electrons or bonds. The energy at which the absorption occurs, as well as the intensity of the absorption, is determined by the chemical environment of the absorbing moiety. Eor example, benzene has several ultraviolet absorption bands due to 7t —> 71 transitions. The position and intensity of two of these bands, 203.5 nm (8 = 7400) and 254 nm (8 = 204), are very sensitive to substitution. Eor benzoic acid, in which a carboxylic acid group replaces one of the aromatic hydrogens, the... [Pg.402]

Electromagnetic radiation (Section 13.1) Various forms of radiation propagated at the speed of light. Electromagnetic radiation includes (among others) visible light infrared, ultraviolet, and microwave radiation and radio waves, cosmic rays, and X-rays. [Pg.1282]

Arrange the following types of photons of electromagnetic radiation in order of increasing energy -y-rays, visible light, ultraviolet radiation, microwaves, x-rays. [Pg.174]

Consider the following statements about electromagnetic radiation and decide whether they are true or false. If they are false, correct them, (a) The total intensity of radiation emitted from a black body at absolute temperature T is directly proportional to the temperature, (b) As the temperature of a black body increases, the wavelength at which the maximum intensity is found decreases, (c) Photons of radio-frequency radiation are higher in energy than photons of ultraviolet radiation. [Pg.174]

Consider the following statements about electromagnetic radiation and decide whether they are true or false. If they are false, correct them, (a) Photons of ultraviolet radiation have less... [Pg.174]


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See also in sourсe #XX -- [ Pg.644 , Pg.654 , Pg.658 , Pg.660 , Pg.746 , Pg.748 , Pg.807 ]




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