Melting point :-102.7 °C (lit.)
Boiling point :-23.2 °C (lit.)
Density :0.6070
vapor pressure :204.6 mm Hg ( −49.5 °C)
refractive index :1.3863
Flash point :-51 °C
solubility :Soluble in alcohol, benzene, and chloroform (Weast, 1986)
form :gas
color :Colorless, flammable gas with a sweet odor
Water Solubility :3,640 mg/L at 20 °C (quoted, Verschueren, 1983)
Henry's Law Constant :0.11 at 25 °C (Hine and Mookerjee, 1975)
Exposure limits :NIOSH REL: TWA 1,000 ppm (1,650 mg/m³), IDLH 1,700 ppm; OSHA PEL: TWA 1,000 ppm; ACGIH TLV: TWA 1,000 ppm (adopted).
InChIKey :MWWATHDPGQKSAR-UHFFFAOYSA-N
CAS DataBase Reference :74-99-7(CAS DataBase Reference)
NIST Chemistry Reference :Propyne(74-99-7)
EPA Substance Registry System :Propyne (74-99-7)

Symbol(GHS):
Signal word:	Danger
Hazard statements:	Code Hazard statements Hazard class Category Signal word Pictogram P-Codes H220 Extremely flammable gas Flammable gases Category 1 Danger P210, P377, P381, P403 H280 Contains gas under pressure; may explode if heated Gases under pressure Compressed gas Liquefied gas Dissolved gas Warning P410+P403 H335 May cause respiratory irritation Specific target organ toxicity, single exposure;Respiratory tract irritation Category 3 Warning
Precautionary statements:	P210 Keep away from heat/sparks/open flames/hot surfaces. — No smoking. P410+P403 Protect from sunlight. Store in a well-ventilated place.