Question

Section/Group: Post-Lab: Experiment 8 1. Draw the structure of the major product that would be obtained from the dehydration of 3. 5-dimethylcyclohexanol 2. In what way did the use of the sodium chloride solution and the separating funnel assist to purify the cyclohexene? See Figure 8.12. Initial distilate with NaCl for pre-drying Upper organic layer (mostly cyclohexene) OG79 Nach NS CH Na co Na Lower aqueous layer (mainly H,0) opangoסניוור CH SCH Figure 8.12. Sodium Chloride for pre-drying. Tests for Unsaturation 147 Experiment

Answer 1

2 PAGE NO dehydration Qidh of 3,5-dimethyl cyclohexanol. CH3 3,5-dimethylcyclohexene Since collection vial contains cyclohexene, water and small amount of Other impuuttia Water present in it will interfere" with distillation as water will co-distill and will not separate, prior to finial. distillation All water must be removed. This is lachieved in two steps frist one is Mix well the sample with aqueous saturated Nacl. at will help in removing the aqueous. layer. It is a pre drying step that I removes maximum of water Anhydrous Calcium chloride is an inorganic during agendg _binds intract dingly with water and this removes the to traces of water left from the solution Around after five minutes, solution is separated from pellet and then transfer to dry fractional distillation, Aparatu

PAGE No sal distillato Final distillation - To achieve distillation is carried out at final dut a slow rat To ensure that the last fraction collected in the form of product is relatively Cyclohexene, the fraction is collected over a narrow range at the polling point of cyclohexene. Purity of cyclohexene is estimated by gas chuomatographic analysis Cyclohexanol + H ₂ POA . -OH Lyon heat +H3 POy heat Cyclohexanol Cyclohexene