Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Electromagnetic radiation visible

List these three types of radiation—infrared. X-ray, and radio waves— in order of 38. List these three t5q>es of electromagnetic radiation— visible, gamma rays, and microwaves— in order of ... [Pg.316]

Electromagnetic radiation of which visible light is but one example has the properties of both particles and waves The particles are called photons, and each possesses an amount of energy referred to as a quantum In 1900 the German physicist Max Planck proposed that the energy of a photon (E) is directly proportional to its frequency (v)... [Pg.520]

Electromagnetic radiation (Section 13 1) Vanous forms of ra diation propagated at the speed of light Electromagnetic radiation includes (among others) visible light infrared ul traviolet and microwave radiation and radio waves cos mic rays and X rays... [Pg.1282]

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]

Dyestuff organic chemistry is concerned with designing molecules that can selectively absorb visible electromagnetic radiation and have affinity for the specified fiber, and balancing these requirements to achieve optimum performance. To be colored the dyestuff molecule must contain unsaturated chromophore groups, such as a2o, nitro, nitroso, carbonyl, etc. In addition, the molecule can contain auxochromes, groups that supplement the chromophore. Typical auxochromes are amino, substituted amino, hydroxyl, sulfonic, and carboxyl groups. [Pg.351]

UV Radiation Electromagnetic radiation in the wavelength range of approximately 4 X 10 to 5 X 10 m, i.e., between visible light waves and X-rays. [Pg.1484]

Visible light, X rays, microwaves, radio waves, and so forth, are all different kinds of electromagnetic radiation. Collective )-, they make up the electromagnetic... [Pg.418]

Electromagnetic radiation of frequency 1 Hz pushes a charge in one direction, then the opposite direction, and returns to the original direction once per second. The frequency of electromagnetic radiation that we see as visible light is close to 1015 Hz, and so its electric field changes direction at about a thousand trillion (1015) times a second as it travels past a given point. [Pg.128]


See other pages where Electromagnetic radiation visible is mentioned: [Pg.17]    [Pg.1]    [Pg.290]    [Pg.305]    [Pg.17]    [Pg.1]    [Pg.290]    [Pg.305]    [Pg.151]    [Pg.1385]    [Pg.521]    [Pg.370]    [Pg.372]    [Pg.383]    [Pg.669]    [Pg.290]    [Pg.1]    [Pg.3]    [Pg.440]    [Pg.114]    [Pg.422]    [Pg.423]    [Pg.449]    [Pg.371]    [Pg.161]    [Pg.350]    [Pg.176]    [Pg.429]    [Pg.450]    [Pg.163]    [Pg.166]    [Pg.521]    [Pg.521]    [Pg.506]    [Pg.709]    [Pg.777]    [Pg.1221]    [Pg.1222]    [Pg.1224]    [Pg.646]    [Pg.646]    [Pg.128]   
See also in sourсe #XX -- [ Pg.644 , Pg.645 , Pg.646 , Pg.658 , Pg.666 , Pg.746 ]




SEARCH



Electromagnet Electromagnetic radiation

Electromagnet visible

Electromagnetic radiation

© 2024 chempedia.info