Consider the reaction : A+B 2 AB. A calibration plot was constructed using x as the concentration for AB in M and y as the absorbance value of AB, it provided the linear equation : y=25x+0.0008. Determine the concentration of AB in M if the absorbance value is 1.22. Round and report your value to the THIRD decimal place. Numeric value only, no unit. No new data to s

You begin preparation of the calibration curve to measure absorbance vs concentration of FeSCN2+. To do so, you add 2.422 mL of 0.200 M Fe(NO3)3 to a cuvette and then directly add 215 µL of 0.001 M KSCN. What is the resulting concentration of FeSCN2*, assuming complete conversion of SCN' to FeSCN2+? Enter your answer in units of mM to four digits after the decimal.

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A student prepared four standard solutions of (NH4)2Fe(SO4)2 and measured their absorbance at 505 nm.  She created a calibration plot with the best-fit line of y = 9372 x + 0.0539.  She measured the absorbance of her diluted unknown sample solution as (4.69x10^-1) nm.  If she prepared her diluted sample solution by diluting 10.00 mL of the original solution to a total volume of 50.00 mL with deionized water, what is the concentration of Fe2+ in her original solution?  Answer in units of M. Note: Your answer is assumed to be reduced to the highest power possible.

The glucose content of samples can be determined using Nelson’s test. The equation of the line for the standard curve prepared for varying concentrations of glucose is y = 3.0x + 0.2. Based on this information, determine the glucose concentration (in M) of a mango preserve having an absorbance reading of 0.891.

Sally obtains a standard calibration curve for their assigned food dye by plotting absorbance versus concentration (in M) of known solutions and finds the following slope and intercept: y = 1.667x + 0.003   Sally finds that her original Kool-aid sample is too concentrated, so they dilute it by transferring 4.00 mL of the original Kool-aid sample into a new container and diluting to a total volume of 47.00 mL. If the absorbance of the dilute Kool-aid sample at the appropriate wavelength for their assigned dye is 0.457, determine the concentration (in M) of the assigned food dye in the original Kool-aid sample. Report your answer with three places after the decimal.

From the following data, calculate the concentration of the analyte in the sample read at 700 nm: Absorbance of unknown sample = 0.807 Absorbance of a 130 mg/dl standard = 0.234 Do not answer in image format. Maintain accuracy and quality in your answer. Answer completely.

The absorbance of a cationic iron(II) sample solution was measured in a spectrophotometer, but the instrument returned an error because the absorbance was too high. The sample was then diluted by using a pipette to take 100.0 μLμL of the sample and injecting it into a cuvette already containing 2.00 mLmL of water (total volume is 2.00 mLmL + 100.0 μLμL). The absorbance value of the diluted solution corresponded to a concentration of 7.71×10−6  M M . What was the concentration of the original solution? Express the concentration to three significant figures with the appropriate units.

1. An unknown sample of Cu2+ gave an absorbance of 0.262 in an atomic absorption analysis. Then 1.00 mL of solution containing 100.0 ppm Cu2+ was mixed with 95.0 mL of unknown, and the mixture was diluted to 100.0 mL in a volumetric flask. The absorbance of the new solution was 0.500. a) Denoting the initial unknown concentration as [Cu2+]i, write an expression for the final concentration [Cu2+]f, after dilution. Units of concentration are ppm. b) In a similar manner, write the final concentration of added standard Cu2+ designated as [S]f. c.) Find the [Cu2+]I in the unknown

Table 1. pH of water samples Sample No. Water Samples pH 1 Tap water from household 6.59 2 Water from creek 7.35 3 Water from river 7.35 4 Unknown sample 7.00 Table 2. Absorbance of Samples Table 3. Calibration Curve Data* Sample No. Absorbance Absorbance 3- Concentration of PO4 Ions, ppm (1 pt each) 1 1.33 1.0 0.050 2 3.26 2.0 0.093 0.89 3.0 0.137 4 0.099 4.0 0.185 5.0 0.230 *Provided by the instructor II. Graph Determination of Phosphate Concentration 3- 1. Using Excel, plot the concentration of PO4* (x-axis) vs. absorbance (refer to Table 3) The olot must show the equation of the best-fit (or trend) line of the graph. Attach the graph below