1. You need to analyze a mixture of alkanes. Which separation method will you choose and why? Consider two cases:
a). mixture of low molecular weight alkanes, less than 15 carbons in the molecule;
b). mixture of compounds with more than 20 carbon atoms in the molecule (paraffins).
2. A solution UV transmittance is 35% at 260nm. Calculate the transmittance if you dilute 25 mL of the solution to 75.0 mL?
3. On size-exclusion chromatogram you have three peaks (2.9, 3.5, and 4.8 min). Column dead volume is 12 mL, and flow rate 4 mL/min. Are your separation conditions fit for size-exclusion requirements? Explain why.
4. 50 mL of 0.1M aqueous solution of some organic compound was brought in contact with 7 mL of octanol at 20 oC. After equilibration GC analysis of octanol phase shows component concentration of 0.4M. What is the partioning coefficient of this component?
5. Two peaks on chromatogram have retention factors k1 = 4.1 and k2 = 5.9. Column efficiency is 2000 theoretical plates, Void volume is 1 mL. Calculate the resolution between these compounds.