<[email protected]> wrote: >That is the absolute upper limit to what a hydride can produce. 1430 J/g. > >No chemical system can produce more than ~4 eV/atom which is close to what > >the heat of formation of water is. > > Formation of 1 molecule of liquid water from Hydrogen and Oxygen gasses > yields > 2.96 eV. >
Right. Yes. Burning a diamond produces ~4 eV per carbon atom, I believe. That is the maximum of any chemical reaction because diamonds have more electron bonds per atom than any other common material. That is more energy per atom but less per gram of fuel than hydrogen, because hydrogen is lighter. H2 + O2 make the best fuel per unit of mass. Someone told me years ago there are a few exotic rocket fuels that might reach 8 eV/atom, but nothing has actually been demonstrated. Rockets propelled by burning diamonds would be kind of neat! - Jed
