Question Four a) The concentration of As(III) in water can be determined by differential pulse polarography in IM HCI. The initial potential is set to-0.1 V versus the SCE, and is scanned toward more negative potentials at a rate of 5 mV/s. Reduction of As(III) to As(0) occurs at a potential of approximately -0.44 V versus the SCE. The peak currents, corrected for the residual current, for a set of standard solutions are shown in the following table. ip (µA) [As(III)] M 1.0 x 10-6 0.298 3.0 x 10-6 0.947 6.0 x 10-6 1.83 9.0 x 10-6 2.72 i. Plot the graph of [As (III)] vs ip and use linear regression to obtain the best fit line for the data obtained ii. What is the calibration curve equation. iii. What is the concentration of As (III) in a sample of water if the peak current under the same conditions is 1.37 µA? b) What is the principle of couloemetry

Question Four a) The concentration of As(III) in water can be determined by differential pulse polarography in IM HCI. The initial potential is set to-0.1 V versus the SCE, and is scanned toward more negative potentials at a rate of 5 mV/s. Reduction of As(III) to As(0) occurs at a potential of approximately -0.44 V versus the SCE. The peak currents, corrected for the residual current, for a set of standard solutions are shown in the following table. ip (µA) [As(III)] M 1.0 x 10-6 0.298 3.0 x 10-6 0.947 6.0 x 10-6 1.83 9.0 x 10-6 2.72 i. Plot the graph of [As (III)] vs ip and use linear regression to obtain the best fit line for the data obtained ii. What is the calibration curve equation. iii. What is the concentration of As (III) in a sample of water if the peak current under the same conditions is 1.37 µA? b) What is the principle of couloemetry

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter11: Dynamic Electrochemistry

Section: Chapter Questions

Problem 10P

See similar textbooks

Similar questions

In a voltammetric analysis of an analyte the output plot is: Current-potential curve Current-time curve Charge-time curve
A solution of altura red of concentration 307 ppm gives an absorbance of 0.616. What concentration is a solution of allura red which gives an absorbance reading of 0.261? The same cell (cuvette) with a path length of 1.000 cm is used for both readings. Report your answer to the nearest whole number without units? Hint: A=abc, where c can have any concentration units. dont provide handwriten solution
Topic: Electrochemical Techniques What would be the expected limiting current of the reduction of 2.5x10-4 M Pb2+ using the DME charateristics (m=2.5 mg/s & t=5s)? Assume that the coefficient of diffusion for Pb2+ is 1.00x10-5 cm2/s.
An unknown sample of Librium was analyzed using polarography. A 50 mL sample containing the sample gave a limiting current of 0.40 uA. 5.00 mL of 5.00 mM standard Librium solution was added to the 50 mL sample and diluted to 100 ml. The wave height of the standard containing the sample gave a limiting current of 0.95 UA. What is the concentration of Librium in the unknown sample?a. 0.11 mmb. 0.21 mMc. 0.55 mmd. 2.0 mme. none of these
Si sample of unknown doping, Hall measurement has been made and thefollowing information obtained: W = 0.05 cm, A = 1.6 x 10-3 cm2, I = 2.5 mA, and the magnetic field is 30 nT (1T = 10^-4 Wb/cm2). If a Hall voltage of +10 mV is measured, find the Hall coefficient, conductivity type, majority carrier concentration, resistivity, and mobility of the semiconductor sample. Plz, don't answer who don't know exactly.
An unknown cadmium(II) solution was analyzed. A 25.00-mL sample of the unknown solution produced a diffusion current of 1.86 mA. Following addition of a 5.00-mL aliquot of 0.00212 M Cd2+ standard solution to the unknown solution, a diffusion current of 5.27 mA was produced. A) What type of electroanalytical method was used? B) What type of calibration method was used? C) What is the molar concentration of Cd2+ in the unknown solution?
For a nitrate ion selective electrode, the selectivity factor for nitrite over nitrate is 0.062 and that for nitrate over perchlorate is 990. What is the percent error in the measurement of a 1.50 mM nitrate solution in the presence of each interfering ion at a concentration of 0.10 mM? Please answer very soon will give rating surely Complete Answer needed
You prepare a saturated LiF solution at room temperature and use a fluoride ion selective electrode to measure [F-] = 0.0429 M. What is the Ksp for this product?
Which are true for polarography? I Polarography is amperometry conducted with a dropping Hg electrode. II The diffusion current in the plateau region of the polarographic wave is proportional to the concentration of the analyte and is used for quantitative analysis. III The half-wave potential for maximum current is characteristic of a given analyte in a given medium and can be used for qualitative analysis for the analyte. IV Fresh Hg drops give reproducible results. V Polarography is used to primarily to study oxidations Hg may reduce when studying reductions. A.I, III, and IV B. II, III, and V C. I and V D. III, IV, and V E. II, III, and IV
We apply a voltage of 10 V to Fcc an aluminum wire 2 mm diameter and 20 m long , if 10 % of the valence electrons carry the electrical charge , the parameter of cell α = 0. 4049 nm , electrical conductivity σ = 3.77 ×105 cm-1. Ω-1. , calculate the average drift velocity of the electrons in m/sec