Introduction: In this lab we separate a mixture of benzoic acid and acetanilide. We were given 25ml of the mixture of benzoic acid and acetanilide and 14ml 1.5m KOH. We added a mixture of the benzoic acid to the KOH, which formed sodium benzoate an aqueous layer and also formed an organic layer which we separated by decanting. We added HCL to the aqueous solution and a white precipitate was formed. The white precipitate turned blue litmus red so therefore it is acidic in nature. We then added 0.5g magnesium sulfate to the organic layer, a white precipitate was formed we then decanted in a separating funnel with a white cotton wool. The clear precipitate that was formed we put into our fractional distillation set up. We put the clear solution into the round bottom flask and we heated it. The clear solution evaporated and passed through the condenser which had water passing through it in and out trying to cool the evaporated solution. We set our temperature and we were watching the temperature. As the temperature was rising we were collecting dichloromethane in the graduated cylinder. The boiling point for dichloromethane is 39.6c when we reached that temperature we stopped boiling and we collected about 12ml of dichloromethane in the graduated cylinder. We kept the residual from the round bottom flask. We also kept the white precipitate that was formed from the aqueous layer we passed it through a filter paper and we left it to dry.
Apparatus: Distilling column, condenser, round bottom flask, separating funnel, pyrexz stopper, thermometer, tubes cotton wool.
Chemicals: Ethanol, water, boiling chips.
Procedure: We connected the Bunsen burner to the gas we then connected the round bottom flask to the distilling column, we connected the distiiling column to a thermometer with a pyrex stopper. We connected the distilling column to the condenser and then connected it to the graduated cylinder.
Results: The total volume of the mixture of benzoic acid and acetanilide was 25ml and we also had a mixture of 14ml 1.5m KOH. We obtained 12ml dichloromethane at 39.6c after heating the organic layer and treating with magnesium sulfate.
Conclusion: We were able to separate the mixture of benzoic acid and acetanilide and we were able to obtain the solution of dichloromethane