A sample is run on a TLC plate and gives a single spot as shown below on the left. However, the solvent was not allowed to run up the plate very far, and so the experiment was repeated with a much larger solvent distance as shown on the right below. What would be the approximate Rf value of the spot for the repeat experiment on the right? solvent line solvent line start line start line 01.0 0.9 © 0.5 0.1

A sample is run on a TLC plate and gives a single spot as shown below on the left. However, the solvent was not allowed to run up the plate very far, and so the experiment was repeated with a much larger solvent distance as shown on the right below. What would be the approximate Rf value of the spot for the repeat experiment on the right? solvent line solvent line start line start line 01.0 0.9 © 0.5 0.1

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

Chapter20: Molecular Mass Spectrometry

Section: Chapter Questions

Problem 20.9QAP

See similar textbooks

Similar questions

1. For determining the %w/w of salicylamide and caffeine in an unknown sample using acetaminophen as an internal standard using a HPLC a) Is it possible to use the λmax (273 nm) of caffeine in the experiment instead of using 254 nm? Explain your reasoning.b) What are some advantages of using the Internal Standard method for quantitation over the External Standard method?c) How is the signal intensity seen in the chromatogram affected by the wavelength used for analysis?
1. Which of the following compounds is separable by a physical method such as distillation? A
Nelson's test was first performed in standard glucose solutions to generate a linear equation to determine the concentration of D-glucose hydrolyzed from the glycogen isolate. The linear equation is constructed by plotting the concentration of standard glucose (in mM) on the x-axis against the absorbance of the resulting mixture at 510 nm on the y-axis. As such, the general form of the linear equation is: Abs = slope (in mM-1) [glucose] (in mM) + y - intercept
1. From spinach, the chromatographic analysis will yield two major substances: (a) B-carotene (C40H56), which will separate from the spinach mixture to form a yellow band, and (b) chlorophyll A (CSSH72MGN4OS), which will separate from the mixture to form a green band. i. Describe the characteristics and draw structures of these molecules. ii. From the spectrophotometric analysis, what wavelength (Amax) would you expect ß-carotene (C40H56) to absorb? What wavelength would chlorophyll A (CssH72MgN4O5) absorb?
How do I solve for [FeSCN2+] heres the formula they provided me and my data but I would like steps on how to solve it and what data I should be using to solve for it u can use any fake numbers you need to help me understand ! I'm confused only by the absorbance part , what number am I using for the absorbance? Is it Fe3+ added to ScN- absorbance values ? also e = 202 and L = 1.0
A student developed a chromatogram and found that the eluent from travelled 94 mm and the Zn^2+ cation travelled 24 mm. In the development of a chromatogram of a mixture of cations, the eluent front travelled 87 mm. if Zn^2+ is a cation of the unknown mixture, where will its band appear in the chromatogram?
A student prepared a cereal sample solution using a procedure similar to that in Lab 5. The original sample solution was diluted by a factor of two, and then the absorbance of the diluted sample solution was measured and recorded as (2.0x10^-1). Use the following calibration plot and the dilution factor to determine the concentration of iron, in unit of M, in the original cereal sample solution. The trendline (linear regression) as displayed on the plot is y = 11898x - 0.0112.
Describe the origin of shot noise in a spectrophotometer. How does the relativeuncertainty vary with concentration if shot noise is the major noise source?
HPLC VFA analysis - why do I get so different peaks for very similar samples?
I need to come up with a protocol of uv-vis spectrophotometer to detect water and chlorine-carbon. Can my solvent be water? What will be my standard?
Let the retention factor of species A be 0.5, while the retention factor of species B be 0.3. If species A moves 1.0 cm how far does species B move? 0.60 cm 0.80 cm 1.0 cm 1.2 cm 1.6 cm
1) Study the chromatograph (below) of a mixture of Compounds A and B, run on the GCs in the teaching labs at CU Boulder. Compound A has the shorter retention time. STAAT 61 1.11 227 RT TYPE AREA XXXX XXXX XXXX AREAS 0.009 55874 44.117 ARIHT 0.61 XX XX XX 1.11 2.27 XX XX XX TOTAL AREA=XX MUL FACTOR=XX 1. What is the retention time of compound A? Compound B? 2. Which compound is present in a larger amount? 3. Which compound has the lower boiling point? 4. What would happen to the retention times of compounds A and B if the column temperature were raised? 5. You suspect that compound B is octane. What can you do to provide supporting evidence for this hypothesis?