A 1.058-g sample of a copper unknown was dissolved in water and diluted to a final volume of 100.0 mL. The sample was analyzed using a UV/VIS spectrophotomete and the absorbance was found to be 0.529. The calibration curve gave a best fit line of A = 8.58 M. Calculate the %/whw) Cu in the sample Give place after the deocima t enter units

A 1.058-g sample of a copper unknown was dissolved in water and diluted to a final volume of 100.0 mL. The sample was analyzed using a UV/VIS spectrophotomete and the absorbance was found to be 0.529. The calibration curve gave a best fit line of A = 8.58 M. Calculate the %/whw) Cu in the sample Give place after the deocima t enter units

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter14: Applications Of Ultraviolet-visible Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 14.12QAP

See similar textbooks

Similar questions

A 50 mL aliquot of river water is treated with a conditioning solution, which is stirred and recorded at 500 nm. The equipment reading indicated 40.5% Transmittance with 1.5 cm optical path cuvettes. Calculate the ppm of sulfate (PM 96 g / mol) in river water if a standard of 3.0x10-5 mol / L of sulfate, under the same conditions, gave 55% Transmittance in cuvettes with 1.5 cm of passage. optical.
The water in Fell city also contains 30 μg/L of chloroform (formed in the water treatment plant), 5 μg/L of chlorpyriphos (a persticide), and 10 μg/L of chromium VI. Given the reference doses below, calculate the total hazard quotient. State which compound is the total HQ is acceptable. References doses (all mg/kg.d): 0.01 for chloroform, 0.0003 for chlorpyiphos, and 0.003 for chromium VI. Answer: 0.66
Anionic surfactants in wastewater are measured spectrophotometrically as methylene blue active substances (MBAS). A volume of a water sample is first reacted with methylene blue, a cationic dye, in a basic buffered aqueous solution. The resulting solution is agitated after the addition of chloroform. The organic layer is then extracted, and the absorbance is read at 655 nm. A standard calibration curve is produced by plotting absorbance vs. concentration for the concentration range between 0 ppm to 2.50 ppm. The line had the following equation: y = 0.286x + 0.009 a. The limit of surfactant content in Philippine class B water is 300 ppb. If a 5 mL aliquot of a 50 mL water sample had an absorbance of 0.084 after MBAS analysis, is the sampled water body suitable for bathing? Support your answer
Calculate the standard deviation of the data below. 2.4 ppm, 2.1 ppm, 2.1 ppm, 2.3 ppm, 1.5 ppm
You are developing a Ca detection method for a graphite furnace AA instrument. Your analysis of ten blank samples gives a standard deviation of 0.265 ppb. To establish your limit of detection (LOD), what concentration of Ca should be spiked into your blanks?
Quinine in a 1.553-g antimalarial tablet was dissolved in sufficient 0.10 M HCl to give 250 mL of solution.A 10.00-mL aliquot was then diluted to 50.00 mL with the acid. The fluorescence intensity for the dilutedsample at 347.5 nm provided a reading of 196 on an arbitrary scale. A standard 100-ppm quinine solutionregistered 125 when measured under conditions identical to those for the diluted sample. Calculate the massin milligrams of quinine in the tablet.
A 0.500g sample is analyzed spectrophotometrically for manganese by dissolving it in acid and transferring to a 250 mL flask and diluting to volume. Three aliquots ae analyzed by transferring 50 mL portions with a pipet to 500 mL Erlenmeyer flask and reacting with an oxidizing agent, potassium peroxydisulfate, to convert the manganese to permanganate. After reaction, these are quantitatively transferred to 250 mL volumetric flasks, diluted to volume and measured spectrophotometrically. By comparison with standards, the average concentration of the final solution is determined to be 1.25 x 10^-5M. What is the percent manganese in the sample?
A method for the detection of morphine is used to generate a calibration curve in which the assay response (y) is plotted versus morphine concentration (x, in mg/L). This gives a straight line with a slope (m) of 0.241 and a y-intercept (b) of 0.011, where y = mx + b. The slope of this line has a standard deviation of ±0.007, and the standard deviation of the intercept is ±0.006. If the sample from an athlete gives a response of 0.506 ± 0.013 in this method, what is the concentration of morphine in the sample and estimated precision of this concentration?
A graphite furnace atomic absorption spectrophotometer (AAS) was used to determine the arsenic (As) concentrations in drinking water. A large set of blank samples yielded an average blank signal of 0.013 and a blank standard deviation of 0.0030. The following data were obtained for a calibration curve. [As] (ppm) 2.0 4.0 6.0 8.0 10.0 Absorbance 0.17 0.28 0.48 0.53 0.72 Using a spreadsheet on an Excell, create a graph of the data using symbols only for the data points. Plot the line on the same graph and include the graph to this question. (a). What is the sensitivity of the method? (b). Calculate the LOD and LOQ for As. (c). A sample of water yielded an absorbance of 0.43. What is the concentration of As in the water?
Organic carbon in seawater can be measured by oxidation to CO2 with K2S2O8, followed by gravimetric determina- tion of CO2 trapped by a column of Ascarite. Water weighing 6.234 g produced 2.378 mg of CO2 (FM 44.010). Find ppm carbon in the seawater.
Suppose that you are trying to measure the concentration of SO2 in air. To do that, you followed the para-rosaniline method. The SO2 was collected in a 10-ml solution of HgCl4 2- then diluted to 25 ml after the addition of the appropriate reagents. The absorbance owas measured at 650 nm in a 2.0-cm cell, yielding a value of 0.535. A standard sample was prepared by substituting a 1.00 mL sample of a standard solution containing the equivalent of 15.00 ppm SO2 for the airsample. The absorbance of the standard is found out to be 0.191. Report the concentration of SO2 in the air in parts per million. The density of air is 1.19 g/L
The method of standard additions was used to determine nitrite in a soil sample. A 1.00-mL portions of the soil extract sample was transferred to four 25-mL volumetric flasks. To each flask, increment volumes of a 1.00 x10-3M nitrite was added according to the table below. A colorimetric reagent was added to each flask to convert the nitrite into a colored product, and finally diluted to volume. What is the concentration of the nitrite in the soil extract based on the absorbance data below (with blank correction included)? Vol. of standard nitrite added, ml Absorbance 5.00 0.079 10.00 0.161 15.00 0.236 20.00 0.318 25.00 0.403