Comparative Properties of Hydrogen and Other Fuels

 

 
Property Units Hydrogen Methane Propane Methanol Ethanol Gasoline
Chemical Formula   H2 CH4 C3H8 CH3OH C2H5OH CxHy (x = 4 - 12)
Molecular Weight [a, b]   2.02 16.04 44.1 32.04 46.07 100 - 105
Density, NTP [3, a, c] kg/m³ 0.0838 0.668 1.87 791 789 751
  lb/ft³ 0.00523 0.0417 0.116 49.4 49.3 46.9
Viscosity, NTP [3, a, b] g/cm-sec 8.81 E-5 1.10 E-4 8.012 E-5 9.18 E-3 0.0119 0.0037 - 0.0044
  lb/ft-sec 5.92 E-6 7.41 E-6 5.384 E-6 6.17 E-4 7.99 E-4 2.486 E-4 - 2.957 E-4
Normal Boiling Point [a, b] °C -253 -162 -42.1 64.5 78.5 27 - 225
  °F -423 -259 -43.8 148 173.3 80 - 437
Vapor specific gravity, NTP [3, a, d] air = 1 0.0696 0.555 1.55 N/A N/A 3.66
Flash Point [b, d] °C <-253 -188 -104 11 13 -43
  °F <-423 -306 -155 52 55 -45
Flammability Range in Air [c, b, d] vol% 4.0 - 75.0 5.0 - 15.0 2.1 - 10.1 6.7 - 36.0 4.3 -19.0 1.4 - 7.6
Auto ignition temperature [b, d] °C 585 540 490 385 423 230 - 480
  °F 1085 1003 914 723 793 450 - 900
Maximum flame velocity in air [2, c] m/s 2.83 0.45 0.46 N/A N/A N/A
  ft/s 9.28 1.48 1.52      
Attachment: 
Notes: 
  • Properties of the pure substance
  • Properties of a range of commercial grades
  • NTP = 20°C (68°F) and 1 atmosphere
  • N/A - Not applicable
Source
"Alternatives to Traditional Transportation Fuels: An Overview." DOE/EIA-0585/O. Energy Information Administration. U.S. Department of Energy. Washington, DC. June 1994
Perry's Chemical Engineers' Handbook (7th Edition), 1997, McGraw-Hill