Question

(f) Sketch an approximation of what the GC chromatogram for your first distillate fraction. Sketch how the chromatogram would have looked based on the following conditions:

(1) there had been twice as much LOW boiling point component in the distillate fraction

(2) a shorter GC column was used instead

(3) the temperature of the GC column had been set at a higher temperature

the following image is my first distillate fracrion

LABEL: Fraction # 2 components : Time Signal 2.855 | 1 . 2865 870 585 ralforral ng 70.90 min sas 588 2935 366 2940 589 590 2945 591 2.950 2955 354 354 Signal 592 693 2980 504 2065 2920 595 2.975 596 597 508 599 2080 2085 2.990 2.995 000 005 010 609 6 3. OSO 3.055 612 415 Time (min)

Answer 1

I think it will be clearer if I explain it, since sketching it will be fairly easy.

1) If there had been twice the amount of low boiling point compound, the area of the peak with the lowest retention time (which is the one with the lowest boiling point) would be twice the area (called "integral" in your graph) compared to what it is in your actual chromatogram.

2) If a shorter column were used, you would have lower retention times for both compounds and a proportional decrease in the distance between your signals. (For example, your peaks would be at 2 and 3 minutes, without changing their order).

3) If the column had been set at a higher temperature, retention times will also be lower and the peaks would be closer to each other, similar as when a shorter column is used.