Ethyl Acetate
Properties
| State | Liquid |
| Color | Colorless |
| Solubility | Slightly soluble in water (83 g/L at 20°C); miscible with most organic solvents |
| Melting Point | -84°C |
| Boiling Point | 77°C |
About Ethyl Acetate
Ethyl acetate is the small ester that earns its keep in every synthetic chemistry lab on Earth — bp 77.1 °C, density 0.902 g/mL, dielectric constant 6.0, and a moderate polarity index of 4.4 that puts it right in the sweet spot for column chromatography. Pair it with hexane in any ratio from 5% to 80% and you get a tunable polarity gradient that resolves nearly any organic mixture polar enough to come off silica. The Fischer esterification that makes it — CH3COOH + C2H5OH ⇌ CH3COOC2H5 + H2O, catalyzed by H2SO4 — is the textbook example of a thermodynamically controlled equilibrium reaction, with Keq around 4 at room temperature, which is why you either drive it with excess alcohol, distill out water with a Dean-Stark trap, or use the Tishchenko route from acetaldehyde dimerization (commercial scale, no water byproduct). For chemistry teaching, Fischer esterification is one of the few reactions where 18O labeling unambiguously settles a mechanism: putting 18O on the alcohol oxygen and tracking where it ends up shows the ester C-O bond comes from the alcohol, not the acid — the acyl oxygen is the leaving group as water. That 18O experiment by Roberts in 1937 was a landmark in physical organic chemistry. In a workup, ethyl acetate is the go-to extraction solvent for moderately polar organics out of aqueous layers — it's denser than ether (so it sits where you expect), low enough boiling to rotovap off in minutes, and miscible with hexane for transferring product onto a column.
Where you'll encounter it
If you've ever run a TLC or done an aqueous workup, you've used ethyl acetate — typical lab consumption in a working synthesis group is gallons per week, and it's the second-most-used organic solvent after dichloromethane (which it's gradually replacing for environmental reasons). Outside the lab, it's the dominant solvent in nail polish remover (the pear-drop smell), in the European decaffeination process for coffee (the "naturally decaffeinated" label means swiss-water or ethyl acetate, never methylene chloride), and in flexographic printing inks for food packaging. It also shows up at home as the smell of overripe bananas and as a major aroma compound in young red wines — at low concentrations it's fruity and pleasant, but above 200 mg/L in wine it's a classic fault that smells like solvent.
Common Uses
- Default extraction solvent for aqueous workups in organic synthesis
- Mobile-phase component in silica column chromatography (paired with hexane)
- Decaffeination solvent for coffee and tea in the European "natural" process
- Active solvent in nail polish remover and many cosmetic formulations
- Fast-evaporating solvent in flexographic printing inks for food packaging
- Solvent for cellulose nitrate, lacquers, and wood finishes
- Flavor and aroma compound in food and beverage formulations (fruit notes)
- Substrate in undergraduate Fischer esterification and saponification teaching labs
Safety Information
Highly flammable liquid (flash point -4 °C, autoignition 426 °C, explosive range 2.0-11.5%). GHS H225 (flammable liquid Cat 2), H319 (eye irritation), H336 (drowsiness/dizziness). OSHA PEL is 400 ppm (1400 mg/m3) as an 8-hour TWA — at sustained vapor levels above ~1000 ppm you get headache, narcosis, and respiratory irritation. Hydrolyzes slowly to acetic acid and ethanol on water exposure, faster under acid or base catalysis, so old ethyl acetate from an opened drum often smells acidic. Always transfer from drum to bench in a fume hood, ground all metal containers during transfer, and store away from oxidizers.
This safety summary is for educational reference only and may not be complete. It is not a substitute for Safety Data Sheets (SDS), medical advice, or professional chemical safety guidance. Always consult appropriate SDS and qualified professionals before handling chemicals.