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Applying Lab Learning and Techniques to Real-Life Application:Quantification of Cranberry in Cranberry-Apple JuiceMs. Jiaqi Zhang and Ms. Kefan Li(Partner)Submitted to: Ms. Kuljeet Kaur(GTA)CHEM 1045, Experiment No.10, November 16, 2015LABORATORY WRITTEN REPORTHonor Code Signature: Abstract: In this experiment, we determined the percentage of pure, natural Cranberry juice in Cranberry-Apple juice by using an Agilent Cary 60 UV-Vis Spectrophotometer. The use of Spectrophotometer for experimental analysis involves the interaction between electromagnetic radiation with matter. The degree of absorbed radiation measures the transmitted light intensities with a photosensitive detector at specific visible wavelengths. Also the light region used in spectrophotometer is ranged from ultraviolet to infrared region. However, for this experiment, we taken in the visible region since cranberry juice has a visible red color. According to this experiment, we got the wavelength of Cranberry juice is 520 nm, and the absorbance is 1.258. Also we got the different absorbance and wavelength of cranberry juice with different concentration. I.Introduction Cranberries are used to treated many diseases such as urinary tract infections and kidney diseases. Cranberries also contain phytochemicals, such as anthocyanin, whichhave alternating singles and double bonds that give cranberries their deep red color and high absorbance of ultraviolet radiation. In this experiment, we use Spectrophotometer to determine the wavelength and absorbance of Cranberry juice. The light source emits light with a range of wavelength, which ca pass through a monochromator containing a diffraction grating to select a particular wavelength of light. After this experiment, we found the fact that absorbance values of a solution aredirectly proportional to its concentration, which is known Beer-Law. In this experiment, we compare the absorption curve to the absorption spectrum of apple juice, because it is not the deep red color, apple juice have no peak of wavelength andabsorbance.
II. Experimental: Procedure:Before beginning this experiment, we prepared 100ml of cranberry juice, 5ml of cranberry-apple juice, and 25ml of apple juice in separate beaker, and labeled them. • Apple and Cranberry Juice Absorption SpectrumFirst, we prepared 20% Cranberry Juice Diluted Solution by using commercial cranberry juice cocktail (27% cranberry). We added 74ml cranberry juice cocktail into 100ml volumetric flask, and fill up the volumetric flask with deionized water to the 100ml mark. Then we prepared 20% Apple Juice Diluted Solution using commercial apple juice (100% apple) using a smaller volumetric flask. We measured 20ml apple juice and add it into the volumetric flask then do the same thing as last step, then we fill a clean curvet at least three-fourths full with this diluted cranberry juice using a plastic pipet. Then we put those 2 curvets into Agilent Cary 60 UV-Vis Spectrophotometer. Then record the data we got.