Potassium permanganate, KMnO4 is a deep purple solid and solutions of KMnO4 can be analyzed using UV/VIS Spectroscopy. A set of standards is run and the best fit line for the calibration curve is found to be A-0.105(%w/v) + 0.042 A 16.68mL aliquot of an unknown sample containing KMnO4 was diluted to a final volume of 200.05mL. Analysis of the sample at a wavelength of 590nm in a 1.00cm cuvette was found to have a %T - 49.2. Calculate the concentration of KMnO4 (% w/v) in the unknown sample. Give your answer to 2 places after the decimal.

Potassium permanganate, KMnO4 is a deep purple solid and solutions of KMnO4 can be analyzed using UV/VIS Spectroscopy. A set of standards is run and the best fit line for the calibration curve is found to be A-0.105(%w/v) + 0.042 A 16.68mL aliquot of an unknown sample containing KMnO4 was diluted to a final volume of 200.05mL. Analysis of the sample at a wavelength of 590nm in a 1.00cm cuvette was found to have a %T - 49.2. Calculate the concentration of KMnO4 (% w/v) in the unknown sample. Give your answer to 2 places after the decimal.

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

4) 1.580 g soil sample was analyzed for its copper content. The soil sample was completely digested with HNO3-H2O2 mixture and diluted to 50.0 mL with distilled water. 2.0 mL of this solution was taken into a volumetric flask and diluted to 10.0 mL with distilled water. It was analyzed by FAAS system and its average absorbance was calculated as 0.2564. Calibration plot for copper is shown below. Absorbance 0,7 0,6 0,5 0,4 0,3 0,2 0,1 0 10 y = 0,0291x-0,0082 R² = 0,9993 15 Copper, mg/L 20 Calculate the percentage of copper in the soil sample as ppm. 25
A dilute peroxide solution was prepared by quantitatively diluting 10 mL stock H2O2 (MW = 34.0147) to 250mL using a volumetric flask. 50 mL aliquot of the diluted peroxide solution was titrated using the previously standardized KMnO4 in problem 1. Titration of the sample required 29.00 mL titrant and the blank containing 50 mL 1:5 H2SO4 required 0.75 mL of the standard KMnO4. Calculate the concentration in %w/v of the stock H2O2. (Hint: H2O2 produces O2 under acidic condition). Follow sig. Fig
Discuss the advantages, disadvantages, and limitations of the technique of cyclic voltammetry in both qualitative and quantitative measurements.
The following data were obtained from the spectrophotometric titration of Cu(II) and Ca(II) in an unknown solution. A 25.00 mL aliquot of the unknown was taken to which 50.0 mL of ethanolamine buffer and 25.0 mL of distilled water were added. The solution was then titrated with standard 0.2508 M EDTA solution. Plot the recorded data, absorbance against volume of EDTA in mL. Correct the absorbance for volume changes. Calculate the number of moles of Ca(II) and Cu(II) in the unknown sample. Vol of Titrant, mL Vol of Titrant, mL Abs Abs 0.0 0.416 12.5 0.886 2.0 0.415 13.0 0.923 4.0 0.409 13.5 0.958 6.0 0.416 14.0 0.979 8.0 0.535 14.5 0.969 10.0 0.690 15.0 0.971 11.0 0.770 15.5 0.964 12.0 0.840
(Standard addition) Tooth enamel consists mainly of the mineral calcium hydroxyapatite, Ca10(PO4)6(OH)2. Trace elements in teeth of archeological specimen provide anthropologists with clues about diet and diseases of ancient people. Student at Dankook University measured the trace element strontium (Sr) in enamel from extracted wisdom teeth by atomic absorption spectroscopy. Solutions were prepared with a constant total volume of 10 mL containing 0.750 mg dissolved tooth enamel plus variable concentrations of added standard Sr. Added Standard Sr (ng/mL=ppb) 0 2.50 5.00 7.50 10.00 Emission Signal 28.0 34.3 42.8 51.5 58.6 (a) Make a graph showing the experimental data and the calculated straight line. (b) Find the concentration of Sr in the tooth ennamel in parts per million = μg/mL.
The concentration of Na in plant materials are determined by flame atomic emission. The material to be analyzed is prepared by grinding, homogenizing, and drying at 103 ºC. A sample of approximately 4 g is transferred to a quartz crucible and heated on a hot plate to char the organic material. The sample is heated in a muffle furnace at 550 ºC for several hours. After cooling to room temperature the residue is dissolved by adding 2 mL of 1:1 HNO3 and evaporated to dryness. The residue is redissolved in 10 mL of 1:9 HNO3, filtered and diluted to 50 mL in a volumetric flask. The following data are obtained during a typical analysis for the concentration of Na in a 4.0264-g sample of oat bran. Calculate the weight percent of Na in the plant sample.
Use the following atomic masses (in g/mol): Mg = 24.31; O = 16; Ca = 40.08; C = 12.01; Na = 23; H = 1; N = 14.01; S = 32.06; Cl = 35.45; 8.) A sample of Chlorpheniramine Maleate weighing 0.502g was assayed by non-aqueous titrimetry using 22.2mL of HClO4 having a N of 0.1125. Calculate the %P. Each mL of 0.1N HClO4 is equivalent to 19.54mg of Chlorpheniramine Maleate.
A 0.3056 g sample of soluble chloride was analysed gravimetrically for chloride content and 0.7265 g silver chloride was obtained. Calculate the chloride content of the sample in % w/w? MW Cl = 35; Ag = 108
A chemist obtained the following data for percent lindane in the triplicate analysis of an insecticide preparation: 7.23, 6.95, and 7.53%. Calculate the 90% confidence interval for the mean of the the three data, assuming that (a) the only information about the precision of the method is the precision for the three data. (b) on the basis of long experience with the method, it is believed that s---->σ lindane. (c) If s=0.28 is good estimate of σ, how many replicate measurement should be made in order for the mean for the analysis of sample to be within 0.2% of the true mean 90% of the time.
Solutions of cobalt (II) ions have a magenta color with a molar absorptivity constant (e) value at 511 nm of 5.87 M-1cm-1. A 0.500 mL sample is transferred from a 50.0 mL stock solution of Co(NO3)2 and diluted with water to a final volume of 7.50 mL. The dilution had an absorbance value at 511 nm in a standard cuvette (1.00 cm light path) of 0.382. Calculate the mass of Co(NO3)2 contained in the original 50.0 mL stock solution.
10.) A 0.6025 g sample was dissolved and the Ca 2+ and Ba 2+ ions present were precipitated as BaC₂O4.H₂O and CaC₂O4.H₂O. The oxalates were then heated in a thermogravimetric apparatus leaving a residue that weighed 0.5713 g in the range 320 °C to 400°C and 0.4674 g in the range 580°C to 620°C. Calculate the percentage Ba in the sample. a.) What are the approximate values of Vm and Ve for this column? b.) What is the Kd for the unknown protein? c.) What is the approximate molar mass of the unknown protein?
The partition coefficient of ammonia between water and chloroform is wanted to be determined. The necessary quantities of ingredients are taken into the separation funnel, and the extraction process is applied. At the end of the extraction process, 5 mL portions of each of the water and chloroform phases are titrated with 0.1 M HCI in the presence of methyl orange indicator. If the volumes spent at the turning points are 7.2 and 5.1 mL, respectively, calculate the KSU, KLOROFORM (Dispersion coefficient) value.