Methylcyclohexane and methylcyclohexene were separated by gas chromatography in a capillary column, which showed retention times of 10.0 and 10.9 minutes, respectively. The width at base were found to be 0.76 and 0.82

Classify the descriptions based on whether they apply to ion‑exchange, size‑exclusion, or both types of chromatography columns. - Proteins move through the column at rates determined by their net charge. - The gel bed will contain polymer beads with charged functional groups. - Proteins move through the column at rates determined by their size. - The gel bed will contain porous polymer beads. - The properties of the proteins affect the rate at which they migrate. - Proteins are separated based on differences in their amino acid sequences.

The figure below shows a typical separation of several fat-soluble vitamins by HPLC. The x-axis is retention time in minutes.  From the graph try to estimate retention times for peaks 2 and 3. Retention time peak 2 = Retention time peak 3 = Assume that w1/2 is 0.15 minutes for peak 2 and 0.16 minutes for peak 3. Assume that tm is 2.00 minutes. How much time does gamma-tocopherol spend in the stationary phase? From tr and w1/2 find N for the peak that elutes first.  From tr and w1/2 find the resolution of peaks 2 and 3 Calculate α for these peaks. If the flow rate for the column is 1.2 mL/minute what is the retention volume for peak 4?

TLC was used to compare the solubility of two compounds A and B in a solvent system (acetic acid, methanol, H2O). The distances that solvent has moved in the silica gel TLC was 12 cm. and for the compounds were 2 and 8 cm respectively. (a) Calculate the Rf values and which compound is more soluble and which one is more polar. (b) What are the factors affecting the Rf value

QUESTION 5 In a chromatographic separation using a polar stationary phase and a mobile phase composed of 60% hexane and 40% ethyl acetate, two compounds, benzene (peak A) and toluene (peak B), are eluted. The width of peak A at its base is 1.2 min, the width of peak B at its base is 1.3 min, and the retention time of peak A is 5.2 min and peak B is 3.5 min. What is the resolution (Rs) between these two peaks and is it acceptable? R = 1.36. It is not an acceptable resolution. R = 0.74. It is an acceptable resolution. R = 1.36. It is an acceptable resolution. R = 0.74. It is not an acceptable resolution.

A GC-MS was used to analyze an unknown sample. Based off the chromatogram, at least how many different compounds were in this sample? Detector Signal u M Retention Time

A 20-cm long packed column was used to perform the separation of A and B by LC. TRA=16.28 min, TR,B=17.50 min, WA=1.11 min, WB=1.19 min, tм=1.30 min. (a) Calculate the retention factor (k') for A and B. (b) Calculate the average number of theoretical plates and plate height.

1. Methanol and ethanol are separated in a capillary GC column with retention times of 370 and 385 s, respectively, and half widths (W₁/2) of 9.42 and 10.0 s. An unretained butane peak occurs at 10.0 s. Calculate the separation factor and the resolution.