# 4 complete discussion questions show your

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4. Complete Discussion Questions Show your calculations for molarity and include your graph to your lab report, you must show calculated concentration value in your calibration graph: Calculations and Graph
Solution 1: C original=0.40M V original=2mL V2= (2.00mL + 8.00mL) =10.00mL C2= 0.40M * 2.00mL/10.00mL=0.08M Solution 2: C original=0.40M V original=4.00mL V2= (4.00mL + 6.00mL) 10mL C2= 0.40M * 4.00mL/10.00mL=1.6/10=0.16M Solution 3: C original=0.40M V original=6.00mL V2= (6.00mL + 4.00mL) =10mL C2=0.40M * 6.00mL/10.00mL=0.24M Solution 4: C original=0.40M V original=8.00 mL V2= 2.00mL C2= 0.40M * 8.00mL/10=0.32M Solution 5: C original=0.40M V original=10mL V2= (0.00mL + 10.00mL) =10mL C2= 0.40M * 10.00mL/10.00mL=0.4M
0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Absorbance vs Concentration Concentration Absorbance G. C. 1 – 6: DISCUSSION QUESTIONS 1. Your TA will provide you with the correct concentration of the dye in the powdered drink solution. Calculate the percentage error for your data. % error= 0.40-0.24/0.24 = 66.67 66.67% 2. The empirical formula for the Brilliant Blue dye is: C 37 H 34 N 2 O 9 S 3 Na 2 and the formula weight are 792.86g/mol. How would you prepare a 5.25 x 10 -6 M solution of Brilliant Blue dye. How many grams of the dye you need to add to a 1.00 L of water to make this solution. % error = (experimental value - accepted value) accepted value × 100
Molarity of dye prepared= 5.25*10 -6 M= 5.25*10 -6 mol/L 5.25*10 -6 mol of dye is to be added to 1L of water Mass of dye to be added= mol * formula mass= (5.25*10 -6 mol) * (792.86 g/mol) = 0.004162 grams 3. Many dyes used in food product are classified as hazardous chemicals in their pure form. Why, then, can they be safely used in those food products? When the dyes are presented in its pure form, they are hazardous. Dyes are not harmful when they are present within suggest limits. Therefore, food dyes only have a limited amount which causes them not to be harmful. 4. We used 630nm wavelength to carry out the absorbance measurements. What is the color of light that the powdered drink solution primarily absorbs? The color observed in the experiment is blue, because of the dye being a blue hue. The color shown is the emitted color. On a color wheel color opposite to blue is orange, which means orange is the color absorbed by the solution.
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