Question

1) In this experiment, we purified cyclohexene by distillation. Could we have used recrystallization instead to purify? Explain.

2) At the end we stopped the distillation with some material left in the vial. Why is it considered unsafe to distill until dryness?

please help!

Answer 1

1) For the purification of cyclohexene distillation is the best method since it's boiling point is around 83^oC. So we can easily purify the cyclohexene with normal distillation. However recrystallization is not useful for cyclohexene purification due to melting point of cyclohexene is -103^oC so we have go to above -103^oC so it is not economically practically viable

2) We never distil the compound to dryness because during distillation process the chemical may react with atmospheric oxygen and form peroxides these peroxides may explode when they become dry. So for safety precaution generally we stop the distillation process even some residual compound is present the distillation flask