Question

Using the information provided in Lecture #3, compare the amount of energy released by chemical and nuclear reactions, given an identical mass of fuel. Describe two features of nuclear weapons design which reflect the physical differences between chemical and nuclear reactions.

Answer 1

Let's take an example, Heat released or energy released in the chemical equation for the combustion of graphite to produce carbon dioxide is about 393.5 KJ/mol while  nuclear reaction i.e. the radioactive decay of ¹⁴C to ¹⁴N and a β particle release about 1.51×10⁷ kJ of energy. The energy released in this nuclear reaction is more than 10⁵ times greater than that of a typical chemical reaction. This is because total change in mass or conversion of mass to energy in nuclear reactions is much larger than in chemical reactions.

Fission weapons - The uranium nucleus splits into two smaller nuclei. A typical reaction is

It involve a change in an atom's nucleus, usually producing a different element while chemical reactions involve only a rearrangement of electrons and do not involve changes in the nuclei.

In nuclear weapons energy comes from destruction of mass. There is significant mass difference between reactant and product masses.