The crystals were then kept aside for further investigation. Step 2 – Synthesis of Aspirin Warm water was prepared by heating about 100 ml of distilled water in a 400 ml beaker with some boiling shavings to 45.-50℃. 3.0 g of salicylic acid was weighed (salicylic acid formed from step 1) into a 100 ml beaker. In a 10 ml graduated cylinder, 5.0 ml of acetic anhydride was measured and transferred to the 100 ml beaker. 5 drops of concentrated sulfuric acid were also added to the beaker. The mixture was gently heated in the water bath and stirred continuously until all the solid was dissolved. An oil layer also formed during heating of the mixture, but it dissolved with continued heating. After heating for another 5 to 10 minutes, the reaction vessel was removed from the water bath. The reaction mixture was then cooled to room temperature and was not disturbed during the cooling process. Crystals formed, then the beaker was placed in an ice water bath until the liquid thickened to a semi-solid.