A chromatographic separation of four compounds gave the following results. The dead time (tm) is 16.7 sec. (a) What is the capacity factor for analyte 4? (b) What is the resolution factor for analytes 3 and 4?

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Arrange the following in order of increasing Rf on thin-layer chromatography: acetic acid, acetaldehyde, 2-octanone, decane, and 1-butanol.

A purified protein sample was used in a reaction, resulting in an activity of 696.7 nmol min-1. The reaction volume was 145.0 µL and the final volume before loading the plate was 1,050 µL. The total reaction time was 4.25 min. The amount of protein used in the reaction was 4.270 µg. Calculate the specific activity of the sample (in nmol min-1 µg-1).

In your first paragraph you should explain the theory of chromatography in general, and the behind thin layer chromatography in detail. a) Define the terms "stationary phase" and "mobile phase" and describe how the stationary phase and the mobile phase interact with the analyte during a chromatographic separation (for chromatography in general – the same concept applies to thin layer, column, and gas chromatography). b) For what two main reasons would a chemist perform a thin layer chromatography analysis? c) define and describe the process of thin layer chromatography. Include the following terms: marking, spotting, developing, visualizing, and measuring. Include in your description several different ways that the plates can be visualized.

a) Draw a ray diagram for each to locate the image. b) State the characteristics (SALT). *note- diagrams are not to scale (1) (2) (3) (4) PA (5) PA (6) PA (7)

An amino acid mixture consisting of lysine,leucine, and glutamic acid is to be separated by ion-exchangechromatography, using a cation-exchange resin at pH 3.5, with theeluting buffer at the same pH. Which of these amino acids will beeluted from the column first? Will any other treatment be neededto elute one of these amino acids from the column?

TE buffer consists of 10 mM of Tris-Cl, pH 7.6 and 1mM of EDTA, pH 8.0. You need to prepare 3L of TE buffer and you have the following stock solutions: 500 mM Tris-Cl and 1 M EDTA. How will you prepare the 3L of TE? Write work clearly

Plating 0.1 mL of a sample diluted by a factor of 10^(-3) produced 43 colonies. What was the original concentration (OCD) in the undiluted sample?

i) Write down the equation derived from your Excel generated standard curve and describe its components; ii) provide the values of the absorbance data of the unknown sample (do NOT show the absorbance data of the glycine standards). Show all details of the working out of your calculation. Indicate all units! Provide the answer with two decimals precision iii) state the answer in a full sentence. (note: avoid mathematical symbols [=, +, -, etc] in your answer sentence).