Nuclear Energy Size Vs. Chemical Energy Size

Nuclear reactions convert mass into energy.

A chemical reaction involves breaking bonds between atoms in the reactants and forming new bonds to create new products. A nuclear reaction, by contrast, converts mass into energy. Nuclear reactions generate much more energy than chemical reactions.

Types

During a chemical reaction both mass and energy are conserved; the mass of the products equals the mass of the reactants. By breaking bonds with high potential energy then forming new bonds with lower potential energy, the chemical reaction releases energy in the form of heat, light or both, but since energy has merely been transformed from one form of energy to another, energy is also conserved. A nuclear reaction, by contrast, turns mass into energy.

Function

Some chemical reactions can release a great deal of energy -- the decomposition of trinitrotoluene (TNT), for example -- or combustion of gasoline in your car. Nuclear reactions release much more energy, however, because mass and energy are related by the formula E = m (c squared), where "c" is the speed of light in vacuum, a fundamental constant of the universe. Since "c" is a very large number, a very small amount of mass can be converted into a tremendous amount of energy.

Considerations

Not all chemical reactions release energy. Some chemical reactions are endothermic, meaning they absorb heat. If the amount of heat absorbed minus the temperature times the change in entropy of the system is negative, the chemical reaction will be spontaneous, meaning it doesn't need an outside source of energy. Reactions that don't meet this criteria need an outside source of energy in order to occur.

References

• "Chemical Principles, the Quest for Insight, 4th Edition"; Peter Atkins and Loretta Jones; 2008.
• Georgia State University Hyperphysics: Helmholtz and Gibbs Free Energies