Esterification
Title: Esterification
Objective: To recover and calculate the percentage yield of substance by esterification.
Introduction:
When a carboxylic acid reacts with an alcohol, the products are water and ester. The overall reaction is reversible and slow, as soon as the products begin to form, hydrolysis a reverse reaction of esterification occurs. To ensure the reaction is complete an acid catalyst is commonly used. The catalyst is usually concentrated sulphuric acid.
This experiment covered 4 techniques; they are distillation, refluxing, extraction, and esterification. Firstly, esterification and refluxing, the acid and alcohol are first warmed and mixed together with the sulphuric acid catalyst then attached it to a reflux condenser for a period of time. Then extraction, chloroform was added in to the mixture as organic solvent, causing it to form 2 layers. The ester solution layer was then extracted and drying agent was added to remove water. Then the solution undergoes filtration. The last step is the distillation. This step is to distill off impurities by heating the solution; the heat will boil the solution evaporating the impurities, leaving only ester.
Apparatus and materials:
Round bottomed flask, condenser, separating funnel, Bunsen Burner, thermometer, carbon tetrachloride, anhydrous sodium sulphate, benzoic acid, methanol, conc. Sulphuric acid, anti-bumping granules, rotary evaporator.
Procedure: 1) 12.2g of benzoic acid was placed in a 250ml round bottomed flask and 40ml of methanol was added. 2) 5ml of concentrated sulphuric acid was added while swirling the contents of the flask at the same time. 3) Three anti-bumping granules was added to the mixture and was fitted to a reflux condenser. 4) The mixture was refluxed on a steam bath for one hour, after cooling the reaction mixture was poured into a separating funnel containing water. 5) Ester was extracted twice by using organic chloroform. 6) The ester solution was
Objective: To recover and calculate the percentage yield of substance by esterification.
Introduction:
When a carboxylic acid reacts with an alcohol, the products are water and ester. The overall reaction is reversible and slow, as soon as the products begin to form, hydrolysis a reverse reaction of esterification occurs. To ensure the reaction is complete an acid catalyst is commonly used. The catalyst is usually concentrated sulphuric acid.
This experiment covered 4 techniques; they are distillation, refluxing, extraction, and esterification. Firstly, esterification and refluxing, the acid and alcohol are first warmed and mixed together with the sulphuric acid catalyst then attached it to a reflux condenser for a period of time. Then extraction, chloroform was added in to the mixture as organic solvent, causing it to form 2 layers. The ester solution layer was then extracted and drying agent was added to remove water. Then the solution undergoes filtration. The last step is the distillation. This step is to distill off impurities by heating the solution; the heat will boil the solution evaporating the impurities, leaving only ester.
Apparatus and materials:
Round bottomed flask, condenser, separating funnel, Bunsen Burner, thermometer, carbon tetrachloride, anhydrous sodium sulphate, benzoic acid, methanol, conc. Sulphuric acid, anti-bumping granules, rotary evaporator.
Procedure: 1) 12.2g of benzoic acid was placed in a 250ml round bottomed flask and 40ml of methanol was added. 2) 5ml of concentrated sulphuric acid was added while swirling the contents of the flask at the same time. 3) Three anti-bumping granules was added to the mixture and was fitted to a reflux condenser. 4) The mixture was refluxed on a steam bath for one hour, after cooling the reaction mixture was poured into a separating funnel containing water. 5) Ester was extracted twice by using organic chloroform. 6) The ester solution was