SHEET /vs/ethanol-vs-isopropyl-alcohol · COMPARISON
Ethanol vs Isopropyl alcohol: what is the difference?
How they differ
Both are alcohols and both disinfect, and only one is a drink. Isopropyl alcohol has one more carbon and branches, C3H8O against C2H6O, and the body oxidises it to acetone rather than to acetic acid, which is why swallowing it causes a very different and more dangerous picture than drinking ethanol. As a disinfectant, 70 percent solutions of either outperform higher concentrations, because some water is needed for the alcohol to get through a cell wall before it denatures the proteins inside. Isopropyl alcohol evaporates leaving less residue, which is why it is the one used on electronics. The reported oral LD50 values are 5628 mg/kg in rats for ethanol and 4797 mg/kg in dogs for isopropyl alcohol.
Side by side
| Ethanol | Isopropyl alcohol | |
|---|---|---|
| Formula | C2H6O | C3H8O |
| Molecular weight | 46.07 g/mol | 60.1 g/mol |
| Family | Alcohols | Alcohols |
| Everyday group | Food & flavor | Everyday chemistry |
| Functional groups | Alcohols | Alcohols |
| GHS signal wordThe supplier-filed hazard label, not a statement about ordinary use. | Danger | Danger |
| Oral LD50A single acute animal measure. It ranks nothing about human safety. | 5,628 mg/kg (oral, rat) | 4,797 mg/kg (oral, dog) |
| Found in | Beer, Wine, Spirits, Bread, Soy sauce | not recorded |
| CAS number | 64-17-5 | 67-63-0 |
| PubChem CID | 702 | 3776 |
Common questions
- What is the difference between Ethanol and Isopropyl alcohol?
- Both are alcohols and both disinfect, and only one is a drink. Isopropyl alcohol has one more carbon and branches, C3H8O against C2H6O, and the body oxidises it to acetone rather than to acetic acid, which is why swallowing it causes a very different and more dangerous picture than drinking ethanol. As a disinfectant, 70 percent solutions of either outperform higher concentrations, because some water is needed for the alcohol to get through a cell wall before it denatures the proteins inside.
- Is Ethanol bigger than Isopropyl alcohol?
- Isopropyl alcohol is the heavier molecule, 60.1 g/mol against 46.07 g/mol for Ethanol. Ethanol is C2H6O and Isopropyl alcohol is C3H8O.
- Which has the lower reported LD50, Ethanol or Isopropyl alcohol?
- Isopropyl alcohol, at 4,797 mg/kg (oral, dog), against 5,628 mg/kg (oral, rat) for Ethanol. An LD50 is one acute animal measurement, and the two here were not necessarily measured in the same species, so it is a data point rather than a ranking of how dangerous either is to a person.
Read the full records: Ethanol and Isopropyl alcohol.