Practical: Aspirin Flashcards
What are the three stages of making aspirin
-synthesis using reflux apparatus
-recrystallisation
-testing the purity using melting point
When is a reflux apparatus needed
When a solvent/reactant/catalyst is volatile and likely to escape
Why are anti bumping granules used in a reflux apparatus
To prevent large bubbles
How do u separate the product from the reaction mixture
-Solids can be separated by Filtration using a Buchner apparatus
-liquids can be separated by distillation or using a separation funnel
What are some safety measurements
-wear eye protection at all times
-avoid naked flames and wear gloves as Ethanoic anhydride is corrosive and flammable
-salicylic acid is harmful by indigestion and is an irritant
-wear gloves as phosphoric acid is corrosive
What are the three functional groups in aspirin
Catholic acid ester benzene
What mechanism takes place
Nucleophillic addition elimination
If crystals don’t fo after being poured into cold water what could be done
Scratch the surface of the pear shaped flask and use an ice bath
Why is a cold solvent used instead of a hot solvent
Hot solvent will dissolve the aspirin
Why is a minimum of hot solvent used
To make a saturated solution to increase % yield
Why is the solution filtered hot
To prevent aspirin from recrystallising
