Solvent · low polarity
Diethyl ether C4H10O
Also: ether, Et2O
Common extraction/partition solvent in sample prep (liquid-liquid extraction); normal-phase LC as a moderately strong modifier in hexane-based mobile phases; low-boiling GC solvent and headspace/purge diluent. Low viscosity gives low column backpressure, but volatility, low UV transparency and peroxide risk limit routine HPLC mobile-phase use.
Compiled by Hemant RawatLast reviewed July 2026How we verify
Properties
- Formula
- C4H10O
- CAS number
- 60-29-7
- UV cutoff
- 218 nm
- Snyder polarity index (P′)
- 2.8
- Selectivity group
- I
- Eluotropic strength ε° (silica)
- 0.38
- Boiling point
- 34.6 °C
- Viscosity (25 °C)
- 0.224 cP
- Refractive index (nD²⁰)
- 1.3526
- Density
- 0.7134 g/mL
- Water miscibility
- partial
- USP <467> class
- Class 3
Safety
- extremely flammable (bp 34.6 C, flash point -45 C, wide explosive range 1.9-36%)
- peroxide-former (forms explosive peroxides on storage/exposure to air and light)
- CNS depressant / anesthetic (narcotic vapors)
- acute inhalation hazard
- low chronic toxicity (ICH/USP Class 3)
Reference only. Solvents can be flammable, toxic, or peroxide-forming. Always consult the Safety Data Sheet (SDS) and your lab's protocols before handling.
What Diethyl ether mixes with
Miscible with: 1-Propanol, 1,2-Dichloroethane, 1,4-Dioxane, 2-Propanol, Acetic acid, Acetone, Acetonitrile, Benzene, Carbon tetrachloride, Chloroform, Cyclohexane, Dichloromethane, Ethanol, Ethyl acetate, Iso-octane, Methanol, Methyl ethyl ketone, Methyl isobutyl ketone, MTBE, n-Butanol, n-Butyl acetate, n-Heptane, n-Hexane, N-Methylpyrrolidone, n-Pentane, N,N-Dimethylacetamide, N,N-Dimethylformamide, Pyridine, tert-Butanol, Tetrahydrofuran, Toluene, Triethylamine.
Partially miscible with: Dimethyl sulfoxide, Water — mix only over a limited range.
Check any specific pair on the interactive miscibility chart.
Using Diethyl ether in HPLC/GC
Common extraction/partition solvent in sample prep (liquid-liquid extraction); normal-phase LC as a moderately strong modifier in hexane-based mobile phases; low-boiling GC solvent and headspace/purge diluent. Low viscosity gives low column backpressure, but volatility, low UV transparency and peroxide risk limit routine HPLC mobile-phase use.
Its Snyder polarity index is 2.8 (selectivity group I), and its UV cutoff of 218 nm is low enough for most UV detection.See what the polarity index means and the full UV cutoff table.
Sources
- University of Toronto (TRACES) — Burdick & Jackson — Solvent UV cutoff table (absorbance = 1 AU, 1 cm cell)
- Stenutz / L. R. Snyder — Solvent polarity index (P′) and selectivity groups
- NIST — Chemistry WebBook — thermophysical properties (BP, density, refractive index)
- PubChem (NIH/NLM) — Compound property records (physical constants, CAS, formula)
- USP <467> / ICH Q3C — Residual Solvents — solvent classification (Class 1/2/3)
Values are compiled from public references and were last verified July 2026. See ourmethodologyfor how we source and verify. Always confirm critical values against primary references and the SDS.