# In order to find the concentration of yellow and blue

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In order to find the concentration of yellow and blue dye in the green dye mixture we used the absorbance of yellow dye and blue dye at different
concentrations to create a calibration curve. We then plotted the absorbance in the green dye where yellow is absorbed maximally and then where blue is absorbed maximally. Using the slope equation of each trend line and plugging in the absorbance I collected with spectrometer, I was able to calculate that the concentration of yellow dye in the green dye was 6.71 μM and the concentration of blue dye was 9.69 μM . The reading I got for wavelength of the green dye was 492.8 nm. The green we see in the green mixture is the color absorbed least by the blue and yellow dyes. They both absorb other colors more efficiently than green (between the wavelengths of 500-575 nm). The reason we were able to measure the green dye is because the blue dye and yellow dye combined absorb light but the max absorbance wavelength of both dyes are well separated on the color spectrum. They overlap very little. Conclusion: Visible light is a form of electromagnetic radiation located within certain parameters of the electromagnetic spectrum. Visible light has a wavelength range of 400-750 nm. These lengths describe the distance between the crest of each wave. Some of the colors we see as visible light (from low to high wavelength) are violet, blue, green yellow, orange and red. When the electrons in a molecule absorb energy (provided by light) they are “excited” into higher energy orbitals further away from the nucleus. The energy released when an electron falls back to its original orbital appears to us as color. Every molecule has a color it absorbs most efficiently, and the color we see is the color or wavelength that molecule least absorbs (located across from it on the “color wheel”). Beer's Law is an equation that describes the relationship between (light) absorption and molar concentration: A = εbc where A is the absorbance, ε is a constant unique to the (homogeneous) solution, b is the path length through which light is beamed as it passes through the sample, c is the molar concentration in the solution. This equation is based on the fact that the absorbance is proportional to the concentration of a solution. The light that passes through the solution in the cuvette is less intense when it exits the cuvette because of light absorption by the molecules.By plotting a calibration curve consisting of known concentrations and measured absorbance we can extrapolate information about concentrations at higher absorbance or concentrations in different mixtures.
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