Describe7 marksChallenge
The following data were obtained from a gas-liquid chromatographic analysis of a mixture of three alkanes: pentane, hexane and heptane.
| Alkane | Retention time / min | Peak area / arbitrary units |
|---|---|---|
| pentane | 2.5 | 45 |
| hexane | 4.8 | 60 |
| heptane | 8.2 | 30 |
(a) Describe the stationary phase and the mobile phase used in gas-liquid chromatography. (b) Explain the meaning of the term 'retention time' and account for the order of retention times of the three alkanes in terms of their interactions with the stationary phase. (c) Describe how the percentage composition of the mixture can be determined from the data in the table, and state which alkane is present in the highest percentage.