1) What Is Nuclear Fission and Fusion?

Nuclear fission is the destabilization of uranium 235 by adding 1 more neutron making it  U236. The uranium 236 is unstable so it splits apart into krypton  92 and barium 142 and releases 2 more neutrons. This reaction creates a lot of energy. This reaction is also the basis for nuclear bombs, warheads and peaceful use in nuclear power plants.

.235U+1  >   92K + 142B + 2

http://library.thinkquest.org/17940/texts/fission/fission.html

The two lone neutrons continue on and hit two more uranium 235’s making them unstable continuing the chain reaction.  

tp://library.thinkquest.org/17940/texts/fission/fission.html    

NuclearFusion is a nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy. 

 (1.) 1H + 1H > 2H + positron (ß⁺) + neutrino (v)

(2.) 2H + 1H > 3He + gamma ray (y)

(3.) 3He + 3He  >4He + 1H + 1H