Main Question or Discussion Point
Why more energy is released in fusion than fission?
What do you mean by "practically" ? You can still fuse iron and heavier against each other, but you dont gain energy in those processes - you'll loose energy instead. That is why stars starts to "die" when they reach to iron in their core (roughly speaking).Practically, you cannot get fusion, starting from Iron.
Well you CAN fuse higher than iron, the thing is that you cant gain energy anymore. You must add more energy than what is beeing released in the process of fusion. A star must in its core produce energy that can prevent the gravitational collapse of the star (this energy are photons that is produced in the fusion, and they will constitute radiation pressure).Total newb here, so please point out my lack of understanding.
Can elements heavier than iron actually fuse? I thought the way the heavier elements were formed was when a star was about to collapse and iron (or others) picked up stray protons or alphas and became the next element in the line.
Ok, how far off am I?
As far as I know U+U is a standard process in heavy ion collider physics.Ah yes, silly me. When saying fuse, I was thinking of similar atoms(ie iron + iron), not just adding particles (which is, of course, also fusion). Is it possible to get heavier elements to fuse together, or would the energy required be too large?
webelements.com said:Only very small amounts of of element 106, seaborgium, have ever been made. The first samples were made through a nuclear reaction involving fusion of an isotope of californium, 249Cf, with one of oxygen, 18O.
18O + 249Cf -> 263106Sg + 4 1n
Isolation of an observable quantity of seaborgium has never been achieved.
More recently, other isotopes have been made at the Paul Scherrer Institute (PSI) in Switzerland using neon atoms to bombard californium isotopes.
248Cf + 22Ne -> 266Sg + 4 1n
webelements.com said:Only a few atoms of darmstadtium have ever been made, initially through a nuclear reaction involving fusion of an isotope of lead, Pb, with one of nickel, Ni.
208Pb + 62Ni -> 269Ds + 1n