# Lab 5 Report.pdf - Lab 5 Report ANALYSIS OF A COMPLEX...

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Lab 5 Report: ANALYSIS OF A COMPLEX MIXTURE USING SIMULTANEOUS Concentration of stock Benzoic acid: 98.9ppm Stock caffeine: 214ppm Six spectra calibration solutions overlay of benzoic acid and caffeine solutions. Λ max1 : 229.0673676 Λ max2 : 273.05355 Table 1. Raw data for benzoic acid absorbances obtained from Figure 1 at the two wavelengths. Concentrations are calculated from the stock solution and appropriate dilution factors.
Solutions Mg/L (ppm) Absorbance at ymax1 Absorbance at ymax2 B1 3.95 0.4045078456 0.03190077469 B2 7.41 0.6806259155 0.05778567865 B3 9.88 0.8834849596 0.07422804087 Sample calculations: 10mL x 1000uL 1mL = 1000uL = .01L ( 98.8mg L ) (. 0004L) = C2(. 01L) C2 = 3.95mg L
Benzoic Acid absorbances at λmax1 and λmax2 versus concentration. Table 2. Raw data for Caffeine absorbances obtained from Figure 1 at two wavelengths. Concentrations are calculated from the stock solution and appropriate dilution factors. Solutions Mg/L (ppm) Absorbance at ymax1 Absorbance at ymax2 C1 3.21 0.5186601281 0.2265044302 C2 7.49 0.791823864 0.3330471218 C3 10.7 1.127528429 0.4730403423 10mL x 1000uL 1mL = 1000uL = .01L ( 214mg L ) (. 00015L) = C2(. 01L) C2 = 3.21mg L
Coffee absorbances at λmax1 and λmax2 versus concentration.