You Don't Know How "Fun" Aspirin Can Be (yes, you!)...

Summary

The video documents a month-long project to extract aspirin (acetylsalicylic acid) from tablets, purify it, convert some of it into salicylic acid, and test the final product. The presenter uses the project to explain core organic chemistry techniques and concepts, while joking about the tedious work and occasional setbacks.

Process and techniques

1. Crush the tablets. The presenter first breaks the pills into rough pieces, then grinds them into a fine powder. White tablets are chosen to avoid having to remove colored dyes.

2. Extract the aspirin with acetone. The powder is warmed and stirred in acetone. The aspirin dissolves, while tablet fillers such as salts, cellulose, starch, and talc remain suspended. Gravity filtration separates the liquid containing aspirin from the insoluble fillers.

3. Recover the aspirin and acetone. Rather than simply letting the acetone evaporate, the presenter distills it so it can be collected and reused. As the solvent is removed, the aspirin separates from the solution. The recovered solid is rinsed and left to dry.

4. Purify the aspirin by recrystallization. The crude aspirin is dissolved in hot water and then cooled gradually, followed by an ice bath. Aspirin is more soluble in hot water than in cold water, so as the solution cools, aspirin crystallizes while many impurities remain dissolved.

5. Collect and dry the crystals. Vacuum filtration separates the solid aspirin from the water. The crystals are washed and dried. The presenter notes that the drying heat was too high and caused some aspirin to decompose into salicylic acid and acetic acid.

6. Convert aspirin into salicylic acid. The presenter explains that this conversion can occur through hydrolysis using either acid or base. In the experiment, aspirin is heated under reflux with a large excess of water and hydrochloric acid. The excess water helps drive the reversible reaction toward the products, while heating speeds it up.

7. Explain the acid-catalyzed hydrolysis mechanism. The carbonyl oxygen is protonated, water attacks the carbonyl carbon, and further proton transfers make it possible for the ester-like group to leave. The products are salicylic acid and acetic acid, and the acid catalyst is regenerated. The presenter emphasizes that the reaction is an equilibrium and that its steps can also occur in reverse.

8. Recrystallize and isolate the salicylic acid. After reflux, the solution is cooled slowly and then chilled in an ice bath to encourage crystallization. The crystals are collected by vacuum filtration, washed to remove soluble by-products, and dried without heat to avoid further decomposition.

9. Check the product and assess the yield. The presenter reports a final yield of about 54%, noting that the overall yield reflects multiple consecutive steps. To test for salicylic acid, a sample is dissolved in ethanol and treated with dilute iron(III) chloride. The resulting purple color is presented as a positive test for a phenol group: salicylic acid has one, while aspirin does not.

Broader chemistry ideas

• Functional groups shape chemical possibilities. The presenter identifies features of aspirin and salicylic acid, including an aromatic ring and carboxylic acid and ester-related groups. The video describes how changing or removing groups can lead to very different substances.
• Other possible transformations are mentioned. These include decarboxylation of salicylic acid to phenol; routes toward bisphenol A, Tylenol, methyl salicylate (wintergreen), and quinones; and phenol–formaldehyde chemistry associated with early plastics. These are presented as examples of chemical connections, not as experiments performed in the video.
• Laboratory techniques involve tradeoffs and risks. The narration describes difficulties with heating, filtration, and drying, and warns that excessive heat can decompose the product. Hot filtration is described as particularly risky. The acetone transfer is done with a pump rather than by mouth, and the presenter cautions against unsafe handling.

The video ends with humorous “subscribe” and channel-support steps and thanks viewers and patrons for helping fund the projects.

Speakers and sources featured

• CarbonTwelve — the presenter and sole identifiable speaker.
• Background music — audible, but no identifiable speaker or source is named.