One reaction that some small nuclei can undergo is fusion, where two small nuclei collide and form one larger nucleus. This is the type of reaction that powers both H-bombs and the sun. These reactions could offer humanity almost unlimted power, except for the fact that they only occur at tremendous temperature: millions to billions of degrees K.

The energy released by a fusion reaction can be computed by comparing the masses of the products and the reactants and using the mass-energy relationship DE = Dmc² to convert this to energy.

Example: How much energy is released in the fusion of two moles of deuterium to form 1 mole of helium?

2²₁H -> ⁴₂He

Solution: Look up the various masses, compute the change in mass and then use the mass-energy relationship to convert to energy

• ²₁H: 2.01355 amu
• ⁴₂He: 4.00150 amu

DE = Dmc²

DE = Dm*9.00*10¹⁰kJ/g

DE = -0.0256 g* 9.00*10¹⁰kJ/g

DE = -2.30*10⁹ kJ

Information provided by: http://learn.chem.vt.edu