Formic Acid CAS# 64-18-6

Boiling point 

100-101 °C (lit.)

density 

1.22 g/mL at 25 °C (lit.)

vapor density 

1.03 (vs air)

vapor pressure 

52 mm Hg ( 37 °C)

refractive index 

n20/D 1.377

FEMA 

2487 | FORMIC ACID

Fp 

133 °F

storage temp. 

2-8°C

solubility 

H2O: soluble1g/10 mL, clear, colorless

pka

3.75(at 20℃)

form 

Liquid

color 

APHA: ≤15

Specific Gravity

1.216 (20℃/20℃)

PH

3.47(1 mM solution);2.91(10 mM solution);2.38(100 mM solution);

Odor

at 0.10 % in water. pungent vinegar formyl

Odor Type

acetic

biological source

synthetic

explosive limit

12-38%(V)

Water Solubility 

MISCIBLE

λmax

λ: 260 nm Amax: 0.03
λ: 280 nm Amax: 0.01

Sensitive 

Hygroscopic

Merck 

14,4241

JECFA Number

79

BRN 

1209246

Henry's Law Constant

At 25 °C: 95.2, 75.1, 39.3, 10.7, and 3.17 at pH values of 1.35, 3.09, 4.05, 4.99, and 6.21, respectively (Hakuta et al., 1977)

Exposure limits

TLV-TWA 5 ppm (～9 mg/m3) (ACGIH, MSHA, OSHA, and NIOSH); IDLH 100 ppm (180 mg/m3) (NIOSH).

Dielectric constant

58.0（16℃）

Stability:

Stable. Substances to be avoided include strong bases, strong oxidizing agents and powdered metals, furfuryl alcohol. Combustible. Hygroscopic. Pressure may build up in tightly closed bottles, so bottles should be opened carefully and vented periodically.

InChIKey

BDAGIHXWWSANSR-UHFFFAOYSA-N

LogP

-0.540

CAS DataBase Reference

64-18-6(CAS DataBase Reference)

NIST Chemistry Reference

Formic acid(64-18-6)

EPA Substance Registry System

Formic acid (64-18-6)

Risk Statements 

23/24/25-34-40-43-35-36/38-10

Safety Statements 

36/37-45-26-23-36/37/39

RIDADR 

UN 1198 3/PG 3

OEB

B

OEL

TWA: 5 ppm (9 mg/m3)

WGK Germany 

2

RTECS 

LP8925000

F 

10

Autoignition Temperature

1004 °F

TSCA 

Yes

HazardClass 

8

PackingGroup 

II

HS Code 

29151100

Hazardous Substances Data

64-18-6(Hazardous Substances Data)

Toxicity

LD50 in mice (mg/kg): 1100 orally; 145 i.v. (Malorny)

IDLA

30 ppm