1)A chemist runs a mixture of hexane, hexan-1-ol and hexan-2-one through a high-performance liquid chromatography (HPLC) column using a polar mobile phase and a non-polar stationary phase.
Which of the following shows the chemicals in order of their retention times, from lowest to highest?
A. hexane, hexan-2-one, hexan-1-ol
B. hexane, hexan-1-ol, hexan-2-one
C. hexan-2-one, hexan-1-ol, hexane
D. hexan-1-ol, hexan-2-one, hexane
2) The chemist wants to determine the concentration of hexane in the mixture.
Which one of the following will provide information to allow the hexane concentration to be accurately calculated?
A. running a series of known concentrations of hexane through the HPLC column under the same conditions
B. running the HPLC experiment using a non-polar mobile phase and a polar stationary phase
C. using published retention times and peak sizes of standard hexane chromatographs
D. reducing the HPLC column temperature to achieve better separation of the compounds
Solution
3) Linalool, C10H18O, is a colourless oil found in lavender plants. Identify two processes used to obtain purified linalool from crushed lavender. 2 marks
Solution