Question

STAAT」,61 1.11 227 RT AREA 0.61 XXXX 1 X0XX 2.27 XX0XX TYPE ARIHT AREA% 0009 55 874 44.117 TOTAL AREA-XX MUL FACTOR-XX What is the retention time of compound A? Compound B? b. Which compound is present in a larger amount? c. Which compound has the lower boiling point? d. What would happen to the retention times of compounds A and B if the column temperature were raised? e. You suspect that compound B is octane. What can you do to provide supporting evidence for this hypothesis?

Answer 1

a. The retention time of A is 1.11 and retention time of B is 2.27

b. As the area% of A(55.87) is higher than that of B (44.117), compound A is present in higher percentage.

c. Higher the boiling of compound, more will be its retention time. This can be explained as the higher boiling point compounds will have higher polarity and hence they will elude only at the end. Thus, in this system, compound A will have lower boiling point.

d. If the column temperature is raised, compounds A and B will have higher solubility in the eluding solvent and will elude faster. Therefore, the retention time for compound A and B will decrease.

e. To prove the hypothesis, run the column with octane as standard. If the retention time comes around 2.27 ( 2.0-2.4) then this suggests that compound B was also octane and the hypothesis was correct.