Rf values for plant pigments in different seasons of the year?
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Rf values should be the same for the same plant pigments whenever you do the chromatogram. What will change is the pigments present and their amounts.
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Violet is the purple part of the electromagnetic spectrum. It has a wavelength of 430 to 380 nm and a frequency of 700 to 790 THz.\n\nThese value average out at 405 nm and 745 THz.\n\nIf you square root these values, you get approximately 20.12 nm and 27.29 THz.\n\nA wave of wavelength 20.12 nm is in the Extreme UltraViolet range. A wave of frequency 27.29 THz is in the Moderate InfraRed range.\n\nSo the two answers for the square root of purple are EUV and MIR.
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http://chemlab.pc.maricopa.edu/periodic/periodic.html\n\nhttp://www.swansontec.com/selement.htm
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try these\n\nhttp://www.usda.gov/wps/portal/usdahome\n\nhttp://international.ifas.ufl.edu/FOCUSWEB/focusjan04002.htm
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Try Autumnal/Fall colours...\nLight and dark Golds....Burgundy, Creams, Russet...
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http://www.desertusa.com/colorado/coloriv/du_coloriv.html
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Does this really belong in "Botany"?  Or are you just unclear on the chlorophyll concentration in the average human hand?
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Chlorophyll is a green photosynthetic pigment found green plants. Chlorophyll absorbs most strongly in the blue and red but poorly in the green portions of the electromagnetic spectrum, hence the green color of chlorophyll-containing tissues like plant leaves.
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There are actually 2 types of chlorophyll, named a and b. They differ only slightly, in the composition of a sidechain (in a it is -CH3, in b it is CHO). Both of these two chlorophylls are very effective photoreceptors because they contain a network of alternating single and double bonds, and the orbitals can delocalise stabilising the structure. Such delocalised polyenes have very strong absorption bands in the visible regions of the spectrum, allowing the plant to absorb the energy from sunlight.\n\nThe different sidegroups in the 2 chlorophylls 'tune' the absorption spectrum to slightly different wavelengths, so that light that is not significantly absorbed by chlorophyll a, at, say, 460nm, will instead be captured by chlorophyll b, which absorbs strongly at that wavelength. Thus these two kinds of chlorophyll complement each other in absorbing sunlight. Plants can obtain all their energy requirements from the blue and red parts of the spectrum, however, there is still a large spectral region, between 500-600nm, where very little light is absorbed. This light is in the green region of the spectrum, and since it is reflected, this is the reason plants appear green. Chlorophyll absorbs so strongly that it can mask other less intense colours. Some of these more delicate colours (from molecules such as carotene and quercetin) are revealed when the chlorophyll molecule decays in the Autumn, and the woodlands turn red, orange, and golden brown. Chlorophyll can also be damaged when vegetation is cooked, since the central Mg atom is replaced by hydrogen ions. This affects the energy levels within the molecule, causing its absorbance spectrum to alter. Thus cooked leaves change colour - often becoming a paler, insipid yellowy green.
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Paper chromatography is a modern method used separate mixtures. Paper chromatography uses paper as the stationary phase and a liquid solvent as the mobile phase.\n\nYou will use paper chromatography to test food colorings to see if the color results from a single dye or mixture of dyes. If you cannot get food coloring you can use colored felt pens or other water soluble coloring pens. Your exercise is simple but uses very essential principles. An optional part of the activity is to check a household product for the presence of the same dyes that are in food coloring.\n\nThe technique relies on the idea that the solvent and the paper both have an attraction for the components in a mixture. The solvent creeps along the surface of the paper. If a material is placed on one spot on the paper and is soluble in the liquid solvent, the material will be dissolved when the solvent moves over it. The material will move along with the solvent. Each compound in a mixture will have its own characteristic balance of attractions to solvent and to paper, so all will not move at the same speed. Eventually this difference in speed will separate the compounds.\n\nIn paper chromatography when the conditions are kept constant, a particular compound always travels a fixed percentage of the distance traveled by the solvent front. The ratio of the distance the compound travels to the distance the solvent travels is called the Rf value. The symbol Rf stands for "retardation factor" or "ratio-to-front". It is expressed as a decimal fraction. When the conditions are duplicated, the same average relative positions will turn up for the solvent and solute; thus the Rf value is a constant for a given compound. The Rf value is a physical property for that compound. The Rf value is useful in identifying compounds, but other properties should be used in combination with the Rf value to confirm compound identification. Since it is difficult for different laboratories to exactly duplicate conditions for a chromatography experiment, Rf values are more useful for comparisons within one lab than for comparisons of data from different labs.\n\nSubstances that are not colored can also be separated by chromatography. They are detected using ultraviolet or black light. These substances appear to glow in the dark.
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sunlight stimulates photosynthesis and larger amts produce more growth, lesser amts less growth.......Seasonal light changes inc growth in the spring as light hours incresae, and Fall lesser light as days dec in length slow growth. Same goes for daily changes......Strings of Rainy days vs sunny days!!!! Look outside if you live on the Eastern coast of the US......
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Standard Orange:\n#FFA500 or 255 165 000\nDark Orange:\n#FF8C00 or 255 140 000
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Wet soil, Humid atm, Loamy soil, Proper Sunlight.
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chloroplast contains pigments for capturing solar energy for photosynthesis.plant cells absorb light of visible spectrum that have wavelength between 400 to 700 nm. and uv radiation doesnt fall between it so plant cannot absorb this part of ligt rays. if a plant will be subjected only to uv rays then the plant will die.
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C- longer wavelength.  Red is the long (low fequency) end of the spectrum, and violet is at the short end (high frequency).
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I am not sure but here is a site that may help.\nhttp://www.rurdev.usda.gov/
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Use the Wien law:\n\nlambda(angstrom)= 3x10^7 / T(ºK)\n\nIf for sunspot T= 4600ºK, then\n\nLambda= 6520 angstrom , so color umbra is red.