A student tested water with 2% NaCl as a possible solvent for the separation of a mixture that could contain one or more of the following: G3, Y5, R3, and B1. He obtained the chromatogram of the individual dyes and the mixture shown below. solvent front G3 Y5 R3 B1 Mix origin line (a) Measure the distance the solvent front moved. solvent front

A student tested water with 2% NaCl as a possible solvent for the separation of a mixture that could contain one or more of the following: G3, Y5, R3, and B1. He obtained the chromatogram of the individual dyes and the mixture shown below. solvent front G3 Y5 R3 B1 Mix origin line (a) Measure the distance the solvent front moved. solvent front

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

Chapter33: Automated Methods Of Analysis

Section: Chapter Questions

Problem 33.8QAP

See similar textbooks

Similar questions

Qno1: why there is a need of chromatography and chromatography thecniqs. B) when and where we should use normal and reverse phase chromatography
ASSAY Calibration solutions Calibration solutions of naproxen in the range 5 – 25 μg/mL were prepared. Sample preparation 20 tablets weighing 12.3819 g were crushed to a fine powder. A portion of the powder (145.4 mg) was shaken with approximately 150 mL of acetic acid (0.05 M) for 5 min and then made up to volume in a 250 mL volumetric flask (stock solution). Approximately 50 mL of the stock solution was filtered and a 25 mL aliquot was diluted to 100 mL in a volumetric flask. 10 mL of the resulting solution was further diluted to 100 mL with acetic acid (0.05 M). Analysis The standards and sample solutions were analyzed by HPLC under the following conditions: Column: octadecylsilyl (ODS), 4.6 mmx150 mm, mobile phase: acetonitrile : 0.05 M acetic acid (85:15), flow rate: 1 ml/min, UV detection at 243 nm. Results: A calibration curve of concentration versus peak area was constructed for the standard solutions and gave the straight-line equation: y = 3555.6x + 85, r = 0.9999 The area…
A second spectrophotometric method for the quantitative analysis of Pb2+ in blood yields an Ssamp of 0.712 for a 5.00 mL sample of blood. After spiking the blood sample with 5.00 μL of a 1560 ppb Pb2+ external standard, an Sspike of 1.546 is measured. What is the concentration of Pb2+ in the original sample of blood?
Based on the different chromatographic techniques that you have learned, provide a method or describe a procedure how to analyse the following samples: 1. Analysis of dioxin in water by gas-chromatography 2. Analysis of parabens in cosmetic product by gas chromatography 3. Analysis of caffeine in beverage by HPLC 4. Analysis of PCB in water by HPLC
1a) Hexane, CH3(CH2)4CH3, is found to have a long retention time when separated from a mixture. A column with a C18 (18-carbon chain) stationary phase and a methanol-water modal phase is used for the separation. Explain why hexane has a long retention time. 1b)You wish to chromatographically seperate a mixtureof the follwing compunds. Which of the two compounds will be most difficult to seperatate from one another? Why?
A scientist wishes to measure the concentration of methyl benzoate in a plant stream by gas chromatography. He prepares a sample of butyl benzoate to use as an internal standard. The results of a preliminary run, which used a solution known to contain 1.37 mg/mL of methyl benzoate (peak A) and 1.51 mg/mL of butyl benzoate (peak B), are shown. The area of peak A is determined to be 3.40×102 and the area of peak B is determined to be 398 measured in arbitrary units by the computer. To measure the sample, 1.00 mL of a standard sample of butyl benzoate containing 2.49 mg/mL is mixed with 1.00 mL of the plant stream material. Analysis of the mixture gave a peak area of 437 for peak A and 415 for peak B. What is the concentration of methyl benzoate in the plant stream?
Gas chromatography cannot analyze mixtures due to the sensitivity of the instrument. True False
Method used was Volhard Method Sample preparation: 5ml sample diluted in 100 ml. 20ml aliquot was used for analysis. Concentration of AgNO3: 0.0609M Calculate mass of NaCl and % NaCl (w/v)
What type of components /mixtures can be separated by chromatography
A 18 g of unknown organic sample was dissolve in 756 mL of benzene. The boiling point of benzene was increased by 3.36oC. As the first step of analysis, determine the moecular weight of the unknow sample? Kb of benzene= 2.64oC/m Bb of benzene = 80.09 oC density of benzene = 0.874 g/mL at 25 °C Answer in whole number, no units required.
Louie performed paper chromatography to identify which among the four availablereference mixtures — WAR, OFF, YIN, MEW — have the same components as hisunknown sample, GUN. He spotted the standards and the sample in a Whatman No. 1filter paper, which he placed in a developing chamber containing 3% KCl. After 20minutes, Louie obtained the chromatogram below, immediately noting that the distancetravelled by the solvent from the origin is 79.0 mm. On the other hand, the distances (incm) traveled by the developed spots were tabulated as follows.(see attached) Questions: 1. Is the type of paper chromatography performed normal or reversed? Why?2. Calculate the Rf of the spots from the samples. Report your answers in four decimal places.
Following the monograph procedure, a 724-mg of aspirin (MW-180 g/mol) dissolved in 18.5 ml of cold neutralized alcohol. This solution was then initially titrated with 0.101 N sodium hydroxide solution, then later neutralized with 0.104 N sulfuric acid. What is the percentage purity of sample?