Formic Acid — properties & hazards overview

Name: Formic acid Formula: HCOOH CAS: 64-18-6 UN: 1779 (aqueous solutions vary)
WARNING — corrosive acid vapours (pungent). Strong skin/eye irritant; inhalation can cause respiratory irritation. Highly water-soluble → wet scrubbing with alkaline liquor (e.g., NaOH) is effective.
Boiling point
≈ 100–101 °C (anhydrous)
pKa (25 °C)
≈ 3.75
Vapour pressure (20 °C)
≈ 5–6 kPa (indicative)
Water solubility
Miscible (very high)
Toxicity
resp. irritant
Corrosivity
skin/eye burns
Flammability
combustible
Environmental
acidic effluent
PropertyValue / Note
Appearance / odour Colourless liquid; sharp, pungent odour
Density (20 °C) ≈ 1.22 g/cm³ (anhydrous)
Solubility Fully miscible with water; forms strong acidic solutions
Decomposition At elevated T can form CO and CO₂; avoid hot surfaces
Typical sources Chemical synthesis, leather/textile, preservatives, fermentation off-gas

*Values are indicative. Always verify exact data for your specific concentration via current SDS/regulations.

Get in touch with our scrubber specialist

Boost your industrial processes with our advanced wet gas scrubbers. Our specialist is ready to guide you towards efficiency, productivity, and environmental compliance. Connect with us now for expert advice, custom solutions, and quick responses. Let's find your perfect scrubber solution today.

Contact us