3 replies to this topic

[MeridianStarGazer]

Fusion and fission are 2 separate processes for making energy. Can't make energy from iron using either process. But I bet there is a 3rd process that can make energy from iron. It just requires black hole pressures to do so. Maybe mega black hole pressures.

[bunyon]

The iron nucleus is the most stable. Which means it takes energy input to move either direction from there.

[bobzeq25]

The iron nucleus is the most stable. Which means it takes energy input to move either direction from there.

To add some detail..  There is a concept in thermodynamics called "free energy".  The energy available from any process is FE (reactants) - FE (products).  Of all nuclei iron nuclei have the lowest free energy.  Just enough of each kind of nucleon to make everyone as happy as possible.  If iron is the reactant, _any_ product has higher free energy, and the reaction has negative available energy, ie you have to put external energy in to make it go.

 

You can't make energy from iron nuclei.  It's extraordinarily difficult to make energy from water, the free energy of water molecules is unusually low.  So the Internet "make energy from water" deal is a scam.

 

Free energy.  Don't leave home without it.  <smile>

 

https://www.britanni...nce/free-energy

 

The "binding energy" of a nucleon is the inverse.  Here's a chart.  Note that there _is_ energy available from combining 4 helium nuclei to make an oxygen nucleus.  Which is a process that does occur in stars.  There's a large energy barrier in between the helium and the oxygen.  So, the process only works if you have enough energy to get over the barrier.   Which pretty much means being in the inside of a star.

 

https://chemistrypag...of-the-nucleus/

 

Science.  Don't leave home without it either.  Or your home may be in serious trouble.

[Exnihilo]

Fusion and fission are 2 separate processes for making energy. Can't make energy from iron using either process. But I bet there is a 3rd process that can make energy from iron. It just requires black hole pressures to do so. Maybe mega black hole pressures.

Yeah, the only way to get energy out of iron is to drop it into an accretion disk.