A stock solution of Methylene Blue dye has absorbance (A) of 1.692 at 668 nm. How many fold (times) do you need to dilute this solution to obtain a working solution having absorbance of 0.150? How many microliters (ul) of the stock solution will be necessary to prepare 3.5 ml of the working solution? 668/1.692 394.8 fold; 3.5 ml / 394.8 8.87 x 10^-3 ml = 8.87 ul 3.5 ml / 0.150 = 23.3 fold; 1.692 x 23.3 = 39.4 ul 1.692/0.150 = 11.28 fold; 3.5 ml / 11.28 = 0.310 ml = 310 ul

A stock solution of Methylene Blue dye has absorbance (A) of 1.692 at 668 nm. How many fold (times) do you need to dilute this solution to obtain a working solution having absorbance of 0.150? How many microliters (ul) of the stock solution will be necessary to prepare 3.5 ml of the working solution? 668/1.692 394.8 fold; 3.5 ml / 394.8 8.87 x 10^-3 ml = 8.87 ul 3.5 ml / 0.150 = 23.3 fold; 1.692 x 23.3 = 39.4 ul 1.692/0.150 = 11.28 fold; 3.5 ml / 11.28 = 0.310 ml = 310 ul

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

See similar textbooks

Similar questions

The salt content was extracted from a 12.0000g junk food sample. The extract was diluted to 100.00mL. From this solution, 15.00mL was taken and required 23.75mL of a 0.08943M AgNO solution to reach the endpoint. What is the percentage by mass of salt as NaCI (58.45 g/mol) in the junk food sample? (Answer: 6.897% NaCl)
SOLVE STEP BY STEPDO NOT USE CHATGPTMAKE THE RESOLUTION QUICKLY PLEASE 18. How many mL of hydrochloric acid are required to measure to prepare 1 L of a 0.25 M solution if the density of HCl is 1.17 g/mL and its purity is 36%? (PA of H is 1,008 amu, Cl is 35,451 amu)
An analysis of city drinking water for total hardness was done by two students in the laboratory and produced the following results (in ppm CaCO3): Student A: 228.3, 226.4, 226.9, 227.1, and 228.6. Student B: 229.5, 226.1, 230.7, 223.8, and 227.5 what is the coefficient variation?
__________H3PO4______________ + Ca(OH)2 →__________ HOH + Ca3(PO4)2 What is the molar concentration of 325.25 mL H3PO4 is needed to reach the equivalence point with 475.60 mL of 0.465 M Ca(OH)2? Answer: Unit: Label/ID:
Question 4. New December 18, 2020. The nitrite in a series of standard solutions (mg/L, n = 5) are converted to azo dye and the slope of the calibration curve is 2.0 ppm. A 10.00-mL mineral water sample is treated in the same way as standards and diluted to a final volume of 100.00-mL. It gives an absorbance of 0.80. The absorbance of blank solution under the same conditions is 0.10. Calculate ppm (mg/L) of NO2 (46 g/mol) and the molarity of NaNO2 (69 g/mol) in the original sample B I Ss II !!
How many milliliters of an injection containing 1 mg of drug per milliliterof injection should be administered to a 6-month-old child weighing 16 lb toachieve a dose of 0.01 mg/kg? answer: 0.073 mL. what is the full solution?
An unknown sample of Cu2+gave an absorbance of 0.262. Then 1.00 mL of solution containing 100 ppm (ug/mL)Cu2+was mixed with 95.0 mL of the unknown and the mixture was diluted to 100 mL in a volumetric flask with deionized water. The absorbanceof the new solution was 0.500. a.Denoting the initial unknown concentrationas [Cu2+]i,write an expression for the final concentrationafter dilution [Cu2+] b.Find [Cu2+]in the unknown.
For problem 5, the density of the sample is 0.9977 g/mL and the molar mass of calcium carbonate is 100.0 g/mol. 5. As described in Topic 2, the hardness of water is expressed in terms of amount of calcium carbonate according to the ppm expression. a. Calculate the mass of calcium carbonate present in a 50.00 mL sample of an aqueous calcium carbonate standard, assuming the standard is known to have a hardness of 75.0 ppm (hardness du to CaCO3). b.Calculate the number of moles of calcium ions present in this 50.00 mL sample of aqueous calcium carbonate standard. c. The 50.00 mL sample (at pH 10) was titrated with a 0.00500 M EDTA solution, i. Write the balance net ionic equation for the reaction of EDTA4- with a calcium ion. ii. Calculate the number of moles of EDTA4- needed to completely react with calcium ions in the sample. iii.What volume (in milliliters) of EDTA solution would be needed to reach the equivalence point? This problem was partly answered but I am wondering what…
Question 1: A 0.3516 g sample of commercial phosphate detergent was ignited at a heat to destroy the organicmatter. The residue was taken up in hot HCl which converted P to H3PO4. The phosphate was precipitatedas MgNH4PO4.6H2O by addition of Mg2+ followed by aqueous NH3. After being filtered and washed, theprecipitate was converted to Mg2P2O7 by ignition at 1000 0C. This residue weighed 0.2161 g. Calculate thepercent P (30.974) in the sample?Question 2: The sodium and potassium in a sample weighing 0.9250 g are converted into NaCl and KCl salts. Thechloride mixture weighs 0.6065 g. The chloride mixture are then converted to its sulfate form, the mixtureweighing 0.7190g. Calculate the % sodium oxide and potassium oxide in the original sample. Question 3:Calculate the number of mL of ammonia whose density is 0.99 g/mL, 2.3% by weight NH3 which will berequired to precipitate the iron as ferric hydroxide in a 0.74 g sample that contains 22% FeO.
A student needs 50.0 mL of 5.74×10 -4 M FD&C Blue Dye No. 1 solution. If the student has 2.00 mM FD&C Blue Dye No. 1 stock solution to work with, how much of the 2.00 mM solution should be added to the 50.0 mL volumetric flask? Hint, 2.00 mM is 0.00200 M. 14.35 mL 0.06971 mL 3.485 mL 12.85 mL 6.971 mL
Calculate the millimoles in 0.75ml of n-methylaniline. Density 0.99g/ml
What is the concentration in units of grams of dye per liter of solution ,of the dilute dye solution that is produced as follows? transfer 19.53 ml of stick solution (6.10g/L) to a 200.0Ml volumetric flask and dilute to the 200 ml line with deionized water. Correct number of significant figs