Preparation of Aspirin

You are about to prepare 6.0 g of aspirin. Your first task is to select the appropriate apparatus for the reaction.

Which apparatus will you choose?

• Conical Flask
• Beaker
• Round Bottom Flask

You are about to prepare 6.0 g of aspirin. Your first task is to select the appropriate apparatus for the reaction.<img src="https://imgen2.guidechem.com/img/images/2020/8/1/162552110802799.jpg" width="200" height="200" /> Which apparatus will you choose? • [[Conical Flask]] • [[Beaker]] • [[Round Bottom Flask]]

While a conical flask is useful for many reactions, it is not ideal for organic synthesis involving heating because it does not allow for even heating and refluxing of the reaction mixture. <img src="https://www.rsc.a-star.edu.sg/shop/images/thumbs/0017681_F0403.250_01.jpg_600.jpeg" width="300" height="300" /> • [[Choose Again|Preparation of Aspirin]]

A beaker is a common laboratory apparatus, but it is not suitable for organic synthesis involving heating because it does not allow for even heating and the contents can easily boil over.<img src="https://cdn.images.fecom-media.com/FE052967/images/Pyrex%20Glass%20Beaker%20Squat%20Form%201000ml_5sOTF7wHbU.jpg?width=578&height=578&scale=UpscaleCanvas&anchor=MiddleCenter" width="300" height="300" /> • [[Choose Again|Preparation of Aspirin]]

This is the correct choice. A round bottom flask is ideal for organic synthesis as it allows for even heating and is suitable for refluxing the reaction mixture. Now, you need to decide how to heat the reaction mixture. <img src="https://smartlabs.co.za/cdn/shop/products/908f42d4474fc86bc83caf89c32cd842_700x700.png?v=1626950176" width="300" height="300" /> • [[Heat with a Bunsen Flame]] • [[Heat under Reflux using a Heating Mantle]]

Direct heating with a Bunsen burner can cause uneven heating and may lead to the reaction mixture boiling over or decomposing. <img src="https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQpZvOzf9MSkXVwo6wfxpVAg_d0p2HaAz_x68jBObzJmNx5yyhUM6KRT9d3UJLC49-CarU&usqp=CAU" width="300" height="300" /> • [[Choose Again|Round Bottom Flask]]

Heating under reflux ensures that the reaction mixture is heated evenly and prevents loss of volatile components by condensing them back into the reaction flask. Here is a diagram of the apparatus you will use for reflux: <img src="https://www.researchgate.net/publication/287346837/figure/fig2/AS:328154553045003@1455249550560/Schematic-of-reflux-setup.png"width="500" height="500" /> Next, proceed with the first step of the procedure. What will you do first? • [[First Step: Add ethanoic anhydride]] • [[First Step: Add sulfuric acid]] • [[First Step: Warm the mixture]]

You have added approximately 15 cm³ of ethanoic anhydride to 2.0 g of 2-hydroxybenzoic acid in the round bottom flask. Good choice. Next, what will you do? • [[2nd Step: Add sulfuric acid]] • [[2nd Step: Warm the mixture]]

<img src="https://t4.ftcdn.net/jpg/05/34/10/29/360_F_534102964_N7jh6F7u9SN1RozoKWWnm66Zo8QSL42m.jpg" width="80" height="80" />You have chosen to add sulfuric acid first. However, it is important to add ethanoic anhydride to 2-hydroxybenzoic acid before adding the sulfuric acid to ensure proper mixing and reaction. • [[Choose Again|Heat under Reflux using a Heating Mantle]]

<img src="https://t4.ftcdn.net/jpg/05/34/10/29/360_F_534102964_N7jh6F7u9SN1RozoKWWnm66Zo8QSL42m.jpg" width="80" height="80" />You have chosen to warm the mixture first. However, you need to add ethanoic anhydride and sulfuric acid to the 2-hydroxybenzoic acid before heating the mixture to ensure the reaction occurs properly. • [[Choose Again|Heat under Reflux using a Heating Mantle]]

<img src="https://i.pinimg.com/736x/15/35/4c/15354ca8b8cf3712622f2de21997b96c.jpg" width="100" height="100" />You have added a few drops of concentrated sulfuric acid and swirled the mixture thoroughly. Good choice Next, what will you do? • [[3rd step: Warm the mixture]] • [[3rd step: Allow the mixture to cool]] • [[3rd step: Pour into cold water]]

You have chosen to warm the mixture before adding sulfuric acid. However, it is essential to add the sulfuric acid after adding ethanoic anhydride and before heating the mixture to catalyze the reaction properly. • [[Choose Again|First Step: Add ethanoic anhydride]]

<img src="https://i.pinimg.com/736x/15/35/4c/15354ca8b8cf3712622f2de21997b96c.jpg" width="100" height="100" />You have chosen to warm the mixture under reflux for 20 minutes, ensuring the temperature does not rise above 60°C. Good choice. Next, what will you do? • [[4th step: Allow the mixture to cool]] • [[4th step: Pour into cold water]]

<img src="https://t4.ftcdn.net/jpg/05/34/10/29/360_F_534102964_N7jh6F7u9SN1RozoKWWnm66Zo8QSL42m.jpg" width="80" height="80" />You have chosen to allow mixture to cool before heating. The reaction is incomplete. [[Choose Again|2nd Step: Add sulfuric acid]]

<img src="https://t4.ftcdn.net/jpg/05/34/10/29/360_F_534102964_N7jh6F7u9SN1RozoKWWnm66Zo8QSL42m.jpg" width="80" height="80" />You have chosen to pour the mixture into cold water before heating. The reaction is incomplete. [[Choose Again|2nd Step: Add sulfuric acid]]

<img src="https://i.pinimg.com/736x/15/35/4c/15354ca8b8cf3712622f2de21997b96c.jpg" width="100" height="100" />Allow the mixture to cool You have allowed the mixture to cool for a few minutes. Good choice. Cooling the mixture first allows for a more controlled and gradual precipitation process, which is important for obtaining a higher purity of the final product. Next, what will you do? • [[5th step: Pour into cold water]] • [[5th step: Filter the mixture]]

<img src="https://t4.ftcdn.net/jpg/05/34/10/29/360_F_534102964_N7jh6F7u9SN1RozoKWWnm66Zo8QSL42m.jpg" width="80" height="80" />Pouring the reaction mixture into cold water before allowing it to cool can cause the reaction mixture to solidify too quickly, potentially leading to incomplete precipitation of aspirin or the formation of a less pure product. [[Choose Again|3rd step: Warm the mixture]]

<img src="https://i.pinimg.com/736x/15/35/4c/15354ca8b8cf3712622f2de21997b96c.jpg" width="100" height="100" />You have poured the mixture into 25 cm³ of cold water, stirring well to precipitate the impure solid aspirin. Good choice. Next, what will you do? • [[6th step: Filter the mixture]] • [[6th step: Purify the aspirin]]

<img src="https://t4.ftcdn.net/jpg/05/34/10/29/360_F_534102964_N7jh6F7u9SN1RozoKWWnm66Zo8QSL42m.jpg" width="80" height="80" />You have chosen to filter the mixture before pouring it into cold water. However, it is important to pour the mixture into cold water first to precipitate the impure aspirin, then filter to obtain the solid aspirin. [[Choose Again|4th step: Allow the mixture to cool]]

<img src="https://i.pinimg.com/736x/15/35/4c/15354ca8b8cf3712622f2de21997b96c.jpg" width="100" height="100" />You have separated the impure aspirin by filtration. Good choice. Next, you need to purify the aspirin. Which method will you use? • [[Recrystallisation]] • [[Distillation]]

<img src="https://t4.ftcdn.net/jpg/05/34/10/29/360_F_534102964_N7jh6F7u9SN1RozoKWWnm66Zo8QSL42m.jpg" width="80" height="80" />You have chosen to purify the aspirin before filtering the mixture. However, it is essential to filter the impure aspirin first before proceeding to purify it. [[Choose Again|5th step: Pour into cold water]]

You have chosen recrystallisation to purify the aspirin. This is the correct choice. Recrystallisation allows you to obtain pure aspirin by dissolving the impure product in a suitable solvent and allowing it to crystallize. Congratulations, you have successfully prepared and purified 6.0 g of aspirin following the correct procedure! <img src="https://cdn.dribbble.com/users/424937/screenshots/6660260/01-account-created-dribbble.gif" alt="Celebration Image">

<img src="https://t4.ftcdn.net/jpg/05/34/10/29/360_F_534102964_N7jh6F7u9SN1RozoKWWnm66Zo8QSL42m.jpg" width="80" height="80" />You have chosen distillation to purify the aspirin. Distillation is not suitable for purifying solid compounds like aspirin. It is more appropriate for separating liquid mixtures based on boiling points. • [[Choose Again|6th step: Filter the mixture]]