The short answer is that the nuclear forces are several million times as large as the chemical forces.In the case of uranium, a nuclear process is done and that is at least 1 million times as much as most chemical reactions (such as the burning of gas).
It slightly longer:
Nature has 4 forces or interactions with their specific characteristics.
- Gravity: This is the smallest force but it works up to very large distances.
This force ensures that you stay on the ground with both feet (hopefully). When we fall we find the strength always too big but we can easily lift a weight of 1 kg.
And there are many. Thus, light is an electromagnetic wave. An electric motor is based on the magnetic fields that we generate in that engine thanks to the electrical currents.
Furthermore, all chemical reactions, from the biological in our body to the combustion of coal, are also electromagnetic forces.It concerns change on the basis of the electrons that sit around atomic nuclei.
This force is already a whole lot bigger than gravity but it reaches far less distant.You can see that at a magnet. You have to keep it very close to the iron to feel the attraction and when it is in contact, the force is really much larger than with 1 mm of air between them.
So We never get in touch with this, and that is why it is also difficult to make a show.
This is the force that keeps the neutrons and protons together in the atomic nucleus.Since all the protons have the same electrical charge (positive) the electromagnetic force will let them fly apart. However, the weak interaction is stronger at the distances in the atomic nucleus and, if enough neutrons are present, it will keep everything together nicely.
Only work within a proton and neutron.
If we have a chemical reaction then it actually changes something to the energy levels of the electrons and typically energy is released (or we need them) in the Electronvolt scale (eV unit of Energy on atomic scale).
However, if nuclear reactions occur, such as the splitting of the uranium atomic nucleus, there are several million eV free.
So 1 atom undergoing a nuclear reaction will typically release 1 million times (to even several hundred millions) more energy than an atom undergoing a chemical reaction.
And as we know many kinds of chemical reactions there are also a lot of nuclear reactions possible.Splitting uranium-235 is just one of the possible reactions. It is we the reaction used in most commercial nuclear reactors to eventually generate electricity. A nuclear power plant can actually be seen as a large machine that converts the weak interaction into electromagnetic energy.