Chapter 32

Calculate the capacity factor, resolution and number of theoretical plates of two components from a chromatogram. Quinaldine and nicotine have retention times of \(5.9\) and \(6.2\) min, respectively on a \(30 \mathrm{~cm} \times 0.25 \mathrm{~mm}\) id \(\times 0.25 \mu \mathrm{m}\) film thickness DB5 column. If the peak width of quinaldine is \(0.16\) min and for nicotine is \(0.18 \mathrm{~min}\), calculate (a) Capacity factor for quinaldine and nicotine (b) Column resolution (c) Average number of theoretical plates in the column (column efficiency, \(N\) ) per compound. Note: the retention time of the unretained component is \(1.0 \mathrm{~min}\).

Test your knowledge of chromatographic theory - define the following terms: (a) Dead time \(\left(t_{0}\right)\) (b) Retention time \(\left(t_{\mathrm{R}}\right)\) (c) Capacity factor (k) (d) Separation factor \((\alpha)\) (e) Column efficiency \((N)\).

Calculate the resolution and efficiency of two compounds. Compounds \(X\) andY have retention times of \(18.40\) and \(20.63\) min, respectively, on a 30 \(\mathrm{cm}\) column. If the peak widths at the peak bases are \(1.11\) and \(1.21\) min, respectively, calculate: (a) The resolution factor for the two peaks. (b) The efficiency of each peak.

Test your knowledge of detector terminology. Explain what the following acronyms stand for: (a) \(\mathrm{FID}\) (b) \(\mathrm{TCD}\) (c) \(\mathrm{ECD}\) (d) DAD.

Check your knowledge of liquid chromatography detectors. Make a list of the various major types of liquid chromatography detector in order, from highest to lowest sensitivity. Which of these methods is most versatile and why?