You graph the calibration curve of a solution of an unknown metal (we will call it M+) at 400 nm. The graph is shown below. What is the concentration the solution with an absorbance of 0.500 at 400 nm?

In determining the concentration of a sample X, it was found that it has maximum absorbance at 275 nm. Compound X, has molar absorptivity at 275 nm of 8400 L / mol.cm. Using a spectrophotometer with a 1 cm cuvette, an absorbance of 0.70 was found. What is the concentration of compound X in the sample?

2) In a laboratory study, a calibration was performed using NH4C1 to analyze ammonium spectrophotometrically. The results of the study are given below. According to this, when the 5.0 mL sample containing ammonium is completed to 50 mL with pure water, find the amount of NH4 in the sample whose absorbance was found as 0.12 according to the table. (N: 14 g / mol, H: 1 g / mol, Cl: 35.5 g / mol). Concentration (mg/L) Absorbance 0.01 5 0.05 7.5 0.1 10 0.15 12 0.18

A standard curve of absorbance vs. concentration has a linear trendline of y = 0.56x + 0.987. Use this trendline to calculate the concentration of an unknown sample that has an absorbance of 1.245.

Can you help me on questions 2 AND 3

Hh.130.

2. ] You make 150.0 mL of a copper(II) sulfate solution but forget to cover it before leaving for the day. The next class, you measure the volume and find that you only have 132.0 mL remaining. You didn’t record the initial concentration, but you measure the absorbance of the remaining solution at 620 nm and find that it is 0.386. You also construct the following calibration curve for CuSO4: Standard solution Abs620 0.50 M 0.424 0.40 M 0.336 0.30 M 0.247 0.20 M 0.159 (refer to image) a. What is the value for k (in Beer’s Law)? Provide a calculation or graph to support your answer. b. What is the concentration of the (remaining) solution? c. What was the concentration of the original solution from the first class? d. If you removed 7.5 mL from the 132.0 mL solution in the process of measuring the absorbance, how much water should you add to obtain the original concentration that you solved for in part (c)?

Create a calibration curve for the following 4 M concentrations. (0.16 M, 0.080 M, 0.040 M, and 0.016 M.) The data is in the attached image. Note* only use the absorbance points from the highlighted (highlighted in blue) column. It is the column with an absorbance of 442.6.

A solution of a dye was analyzed by spectrophotometry, and the following calibration data were collected using a 1 cm cuvette. *graph in attachemnt*   Using the calibration data above for the dye solution, what is the dye concentration in a solution with an absorbance (A) = 0.52 if it was measured in a 1 cm cuvette?   Group of answer choices 3.0 x 10-6 M 6.0 x 104 M 2.0 x 10-6 M Not enough information is provided.

Please help