section_path: Properties/Combustion
section_name: Combustion
paragraph_text: Combustion
  
  Hydrogen gas is highly flammable:
  
  Enthalpy of combustion: −286 kJ/mol.
  
  Hydrogen gas forms explosive mixtures with air in concentrations from 4–74% and with chlorine at 5–95%. The hydrogen autoignition temperature, the temperature of spontaneous ignition in air, is 500 °C (932 °F).