Propan-1-ol vs Propan-2-ol: Key Differences, Uses & Safety Guide
Propan-1-ol is n-propanol; its –OH group sits at the end of a three-carbon chain. Propan-2-ol is isopropanol, the same chain with –OH on the middle carbon. Both are clear, flammable alcohols, but their distinct structures give them different boiling points, polarities, and reactivities.
Walk into any pharmacy and you’ll grab “rubbing alcohol”—99 % of the time that’s propan-2-ol. Yet the lab next door orders “1-propanol” for solvent work. Because both say “prop,” and both smell like hospital, people swap names and sometimes bottles, risking ruined reactions or skin irritation.
Key Differences
Propan-1-ol: 97 °C boiling point, slightly milder odor, slower evaporation, higher surface tension. Propan-2-ol: 82 °C, stronger scent, rapid evaporation, better grease cutter. Toxicity is similar, but propan-2-ol vapor is more irritating to eyes.
Which One Should You Choose?
Need hand sanitizer, lens cleaning, or PCB flux removal? Pick propan-2-ol for its quick-dry power. For slower-drying inks, pharmaceutical intermediates, or when less inhalation risk matters, go with propan-1-ol. Always check the SDS and fire code.
Can I mix them?
Technically yes, but you’ll create an unpredictable solvent blend that may void warranties or alter reaction yields. Keep them separate.
Is propan-2-ol safe on skin?
Yes, briefly. Repeated use strips natural oils, causing dermatitis. Rinse with water and apply moisturizer after disinfection.