Red light wavelengths

Photon correlation spectroscopy has several important features, most notably the duration of the experiment is short, and it is readily automated so that reliable measurements can be made even by inexperienced operators. The method has modest development costs. Commercial particle sizing systems mostly operate at only one angle (90°) and use red light (wavelength, 675 nm). Usually in these systems the dependence of light-scattering intensity on concentration is neglected. 

Infrared radiation is electromagnetic radiation lying at longer wavelengths (lower frequencies) than red light a typical wavelength is about 1000 nm. A wavelength of 1000 nm corresponds to a frequency of about 3 X 1014 Hz, which is comparable to the frequency at which molecules vibrate. Therefore, molecules can absorb infrared radiation and become vibrationally excited. 

C07-0046. Calculate the energy in joules per photon and in kilojoules per mole of the following (a) red light with a wavelength of 665.7 nm (b) infrared radiation whose wavelength is 1255 nm and (c) ultraviolet light with a frequency of 4.5528 X 10 Hz. 

Under the conditions of low illumination (normally shady light, which has a high proportion of long-wavelength red light), PS I takes electrons faster than PS II can supply, leaving plastoquinone in its oxidized state. As a result, LHCs are dephosphorylated and migrate to the stacked portion of the thylakoid membrane where they drive to PS II. 

Fe( H20)6](N03)2, containing the weak field complex thus should be green, because the weak field would result in the absorption of light of long wavelength, namely, red light. 

So, the [Fe(H20)6]2+ ion will absorb radiation with a wavelength of 780 nm, which is red light in the visible part of the electromagnetic spectrum. 

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