what is the basic difference between nuclear fusion and nuclear fission?

Dear student,

Fission and fusion are different types of nuclear reactions in which energy is released from the high-powered bonds between particles in the atomic nulceus. The atomic nucleus is most stable when binding energies between particles are strongest. This occurs with iron and nickel. For lighter atomic nuclei, energy can be extracted by combining these nuclei together, a process known as nuclear fusion. For nuclei heavier than those of iron or nickel, energy can be extracted by splitting them apart in a process called nuclear fission.

Because the binding force in the atomic nucleus contains enormous energy, fission and fusion can both provide tons of power, in principle. However, practical considerations make the exploitation of nuclear power more difficult than something as simple as starting a fire. For fission, highly purified feedstock, usually uranium isotopes, must be used. Isotopes are favored because their instability makes them easier to break apart. The purification of these isotopes is extremely expensive and requires multimillion-dollar centrifuges.

In fusion, an extremely high threshold energy must be reached to combine atomic nuclei. In nature, the only place where this occurs is in the core of a star. The temperature required is in the millions of degrees. Superheated plasma and the focusing of laser power are two methods to achieve this threshold energy.