Assertion: fuel | /r/HasProperty | hydrogen
Facets:
value: usually
type: DEGREE
Source sentences:
text: A fuel cell is an electrochemical cell that converts the chemical energy of a fuel (often hydrogen) and an oxidizing agent (often oxygen) into electricity through a pair of redox reactions.
text: At the anode a catalyst oxidizes the fuel, usually hydrogen, turning the fuel into a positively charged ion and a negatively charged electron.
text: The most common fuel is hydrogen.