what is the difference between cold fusion and nuclear fission?

Answer 1

Nuclear fusion occurs when two nuclei combine to form a heavier nucleus. For light nuclei, this releases energy. For heavy ones, it requires net energy. Iron is in the middle; it requires energy to either fuse with anything or fission into anything else. The process requires bringing the nuclei into close proximity. This is hard because nuclei all have a positive charge, and like charges repel. Fusion can be accomplished by colliding at high energies (as in a hot plasma), by applying great pressure to the medium the nuclei are in, or by reducing the Coulomb (charge repulsion) barrier by combining one nuclei with a meson instead of an electron to form an exotic sort of atom. The second requires astronomical pressures impossible to obtain on earth. The latter has been referred to as "cold fusion", but cold fusion usually refers to a disreputed process whereby some combination of the second and third methods is supposedly achievable in an electrically stimulated metal lattice, while avoiding the need for expensive and sort-lived mesons. The study of such cold fusion is considered the arch type of "pathological science" and has stimulated the study of such phenomena from a psychological perspective since it has collapsed into a small chose-knit community of "true believers" who interact primarily with themselves on this matter.

Answer 2

Unusual question. Fusion is the process where the nuclei of atoms come together to to form a heavier atom. The usual example is 2 hydrogen atoms fusing together to form helium; as takes place in the sun.
Fission, meanwhile, involves breaking down of heavier atoms into 2 or more lighter ones, as takes place with nuclear weapons.

Now, cold fusion is a theoritical way to get around the energy barries associated with 'hot' fusion. There is much, much more energy in 2 hydrogen nuclei than there is in a helium nuclei. As a result, when hydrogen fuses to become helium, the excess energy is released. This is the source of the heat and light from the sun. However, hydrogen will not fuse under normal conditions. At the nuclear level, the strong force holds atoms together; this force must be over come so that atoms can seperate and reform. The strong force is, well, strong. It requires a lot of energy to start a fusion reaction; more than we are capable of creating (outsiIde of a theromonuclear explosion).

To start a fusion reaction you would need to heat up a very small area to extrodinary temperatures, or compress an amount of hydrogen to extrodinary pressures. Nobody can do this in a controllable fashion. Cold fusion researchers believe they can catalzye the reaction without heat or pressure. This is theoritically possible.

A catalyst is a substance or process that makes an energetically favorable reaction take place. Chemical catalysts are very common (in biology they are refered to as enzymes). Because fusion is engergetically favorable, it might be possible to create a nuclear catalyst to start a fusion reaction. However, no nuclear catalyst has ever been observed.

Be careful of the above answers -- Many are wrong. Cold fusion refers to the process of starting a fusion reaction without all that heat and energy. But the fusion itself is not cold; the reaction will be just as hot as any fusion reaction. Which is, of course, the point. If fusion did not prouce any energy, we certainly could not use it for power, which is the main reason for research into cold and hot fusion.

Answer 3

Cold fusion is a form of nuclear fusion (not fission).

Fission is an atomic nucleus splitting in two (or more) smaller nuclei.

Fusion is small nuclei combining to form a bigger one. Normally, nuclei must be made to smash quite hard in each other for the fusion to occur. You do that with very high pressure or with very high temperature. Millions of degrees.

Cold fusion would be a case of fusion occuring without the need for pressure or temperature. For example, at "room temperature." There was a famous claim made a few decades ago.

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Of course, the expression is also used for activities that have nothing to do with nuclear energy. For example, some kinds of materials are made by "fusing" different plastics together. Most of the time, you have to melt the plastics to mix them. Sometimes, you can mix them at room temperature, in which case it is called cold fusion.

Answer 4

chilly fusion is like doing what the solar does, fusing hydrogen into helium, at room temperature with a catalyst. Nuclear fission is breaking larger atoms into smaller ones. Nuclear fusion is combining smaller atoms right into a much bigger one.

Answer 5

fusion = two nuclei are forced to join together to form a heavier nucleus
fission = the nucleus of an atom splits into two or more smaller nuclei

and fusion can only be reached with really high temperatures, so a REAL cold fusion reaction is kind of the Holy Grail =)

Answer 6

cold fusion is a theoritical method of a sustained nuclear fusion reaction.this is not practically possible since the temperature is too high to keep the reaction under control.

Answer 7

fission is the breaking apart of atoms sending out massive energy
fusion is combining atoms to make energy
cold fusion is where no heat is produced

Answer 8

a heavy deuterion,proton combine at high temp. with release of energy is nuclear fission

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