Lab 6 Notes

At the end of the experiment you will be assessing the purity of your aspirin by measuring its absorbance at 525nm. If the absorbance measurement is found to be 0.040 then what is the % salicylic acid impurity in your aspirin? a. 0.06 b. 0.25 c. 0.15 d. 0.44 e. 0.35

5. A sample of a red dye and a sample of a blue dye both have the same concentration. Their Absorbance is measured using the same spectrophotometer. At a particular wavelength, will both samples give the same Absorbance reading? Why or why not?

E) 1. What is Amax for this compound? 2. What light would you use to analyze this sample? What color is absorbed and what color is transmitted by the sample? 500 700 vamiengthin anctes (aen) apoy ga

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2. You have two solutions of the same compound that are blue. One is very pale and the other is very intense. Absorbance of each solution was measured with a spectrophotometer at the same wavelength at which the solution absorbs. a) Which solution has the higher absorbance? b) Which is the more concentrated solution?

Why were the absorbance measurements recorded at lambda max (504 nm)?   Question 1 options:   at lambda max impurities in the sample do not absorb any light   Because the allura red dye absorbs red color at 504 nm   at lambda max the absorbance is the most sensitive to dye concentration   at lambda max the absorbance is the least sensitive to dye concentration

Two samples were analyzed using a colormeter on a cellphone: one containing only distilled water, and another containing an unknown solution. The distilled water sample had a Red value of 206, while the unknown solution had a Red value of 118. Calculate the absorbance of the unknown solution. -log (4) A = -log a) -0.242 b) 0.573 c) 0.242 d) 0.000 CASAT

2. Plot the following data as absorbance vs concentration of X in excel                       Absorbance, A          Molar Concentrationof X                           0.045                              3.0x 10-4 mol/L                           0.097                              6.2x 10-4mol/L                            0.14                                9.0 x 10-4 mol/L                            0.35                                  2.2x 10-3mol/L                            0.51                                3.2x 10-3mol/L   When plotting in excel make sure that ( in EXCEL, not hand written ) you label each axis and place a title that includes your name ( Mahmoud ) . Perform linear regression on the data.   Use the graph to answer the following questions. a.What is equation of the line for this graph and what is its R2 value?   b.What is the Molar concentration of X when its absorbance is 0.23?   c.A 5.0x 10-3 M solution would have an absorbance of?   d.What would be the…

Predict what a graph of absorbance versus concentration would look like. Sketch your prediction.

S 1:  0   (absorbances)  -   447.30  S 2: 0.127 (absorbances)  - 447.30  S 3: 0.282 (absorbances)  - 447.30  S 4: 0.432 (absorbances)  - 447.30  S 5: 0.576 (absorbances)  - 447.30  S 6: 0.710 (absorbances)  - 447.30 Fill in the tables using the datayou see above

I dont understand what I would do to get 1c

Given the absorbance spectrum shown above for substance A in solution, what wavelength would you choose for absorbance/concentration studies for solutions of A?    A 470 nm  B  520 nm  C  585 nm D   600 nm E   650 nm

please please answer super fast i need it before 9:30pm please answer all

Examine the given Beer's law standard curve for an unknown dye measured in a 1.0 cm cuvette. Absorbance of Unknown Dye at 542 nm 0.5 0.45 0.4 0.35 0.3 0.25 0.2 y = 15200x - 0.018. 0.15 0.1 5.00E-06 1.00E-05 1.50E-05 2.00E-05 2.50E-05 3.00E-05 3.50E-05 Concentration (M) What is the concentration (in M) of a sample of the unknown dye with an absorbance of 0.22 at 542 nm? Type answer: 2.63E-5 Incorrect Absorbance at 542 nm

Examine the given Beer's law standard curve for an unknown dye measured in a 1.0 cm cuvette. Absorbance of Unknown Dye at 542 nm 0.5 0.45 0.4 0.35 0.3 0.25 0.2 y = 15200x - 0.018. 0.15 0.1 5.00E-06 1.00E-05 1.50E-05 2.00E-05 2,50E-05 3.00E-05 3.50E-05 Concentration (M) What is the molar absorptivity (in M-1cm-1) of the unknown dye at 542 nm? Type answer: 0.25 Incorrect Absorbance at 542 nm

Please provide the correct answers based on the following attached data.

How would you calculate Ɛ from the gradient of an absorbance vs concentration plot?

750 400 11. Short answer. Refer to the color wheel on the right. If a solution is illuminated with white light and absorbs all wavelengths between 480 and 560 nm, what color would it appear to be? Violet Red 430 630 Blue Orange 480 590 Green Yellow 560 12. Short answer. You will need the color wheel on the right. Look at the absorption spectrum of the solution shown on the right. What color would this solution be? 800 13. Short answer. Look at the image of a spectrophotometer on the right. Structures/knobs A-E are labeled. Which knob will you have to use to zero the instrument itself? 20D BIOLOG. 14. Short answer. According to Beer's Law, given that Molar Absorptivity and path length is usually constant, Absorbance A is directly proportional to 15. Choose the one answer that fits best. Which of these is not standard components of a spectrophotometer? a. A sample chamber to hold your tube with sample solution b. A light source c. A prism or grating to filter out certain wavelengths of…

Rank these colors from the best to the least absorber of radiation. (Best absorber - I; Least Absorber - IV) WHITE GREEN BLACK  BLUE