Using the chromatogram below calculate the following parameters: a. Capacity factors for both peaks b. Calculate the resolution between both peaks c. Calculate a for peaks 1 and 2 d. Calculate the number of plates for peak 2 Detector Response W₂ Retention Time (mins) 1-5.06 02-321 M-12 W₁ = 1.25 W2-1.31

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?

13. Electrospray time-of-flight mass spectrometry was used to analyze the eluate from a high-performance liquid chromatography separation. The mass spectrum of one chromatographic peak, containing a protein of unknown molecular mass, displays MH peaks at m/z = 5 654.208, 5 277.326, 4 947.590, 4 656.613, 4 397.990, and 4 166.576. Find the average molecular mass (M) of the neutral protein and its standard deviation.

Internal standard. A mixture containing 12.8 mM analyte (X) and 44.4 mM standard (S) gave chromatographic peak areas of 306 for X and 511 for S. A second solution containing an unknown quantity of X plus 55.5 mM S had peak areas of 251 for X and 563 for S. Find [X] in the second solution.

The following chromatogram is obtained for a mixture of substances X and Y. Calculate the resolution of the two peaks. 10 11 12 13 14 Tim e (min) O A. 0.8 О В. 1.7 O C. 1.2 O D. 3.4 O E. 0.4 Instrum ent response in arbitrary units

The following chromatogram is obtained for a mixture of substances X and Y. Calculate the separation factor. Y 1 10 11 12 13 14 Tim e (min) O A. 1.4 O B. 0.4 O C. 0.8 O D. 1.2 O E. 2.1 Instrument response in arbitrary units

For quantitative analysis with gas chromatography: O the area of a peak reported by the instrument for a compound is proportional to the quantity of that compound. O the calculated response factor value for a compound is proportional to the quantity of that compound. O the retention time reported by the instrument for a compound is proportional to the quantity of that compound. O the peak height reported by the instrument for a compound is inversely proportional to the quantity of that compound. O the peak shape reported by the instrument for a compound is proportional to the quantity of that compound.

All types of chromatography depend on partitioning a sample between a stationary phase and a mobile phase. Identify the stationary phase and mobile phase for each of the following types of chromatography. -TLC -GC

1 24) The method of internal standard was used to analyze and measure the concentration of chemical X by GC A known mixture of compounds X and Y (internal standard) gave the following chromatographic results: Compound X Y Concentration (M) 6.3 x 10-8 2.0 x 10-7 a) 2.0 x 10-6 M b) 8.4 x 10-7 M c) 6.6 x 10-7 M d) 4.1 x 10-7 M e) 2.9 x 10-7 M Peak Area 395 787 Then, an unknown was analyzed as follows. 3.0 mL of unknown X was treated with 0.100 mL of 1.6 x 10-5 M Y and the mixture diluted to 10.0 mL final volume. Peak areas were 633 (for X) and 520 (for Y). What is the concentration of X in the unknown. (The original 3.00 sample?)

The figure below shows a portion of a GC chromatogram for a mixture of two aromatic compounds labeled A and B. The separation employed a 2.50 meter packed column under isothermal conditions (90 °C) and a flow rate of 10 mL/min. Detector Signal 300.0 250.0 200.0 150.0 100.0 50.0 0.0 1.0 1.1 Unretained 1.5 time (min) Find the times that components A and B spend in the stationary phase. 2.0