why splitting a tiny particle can cause such a devastating blast
You actually split a lot of them at once.
Each one goes from a higher energy state to a lower energy one, and that releases energy because of conservation of energy. This energy is, compared to chemical explosives, *gigantic*. So there is a big boom.
Because there are a lot of them.
It might be better to not think of the size of individual atoms but how many of them there are in a give volume or mass of fuel.
I mean hydrocarbon molecules and oxygen molecules are pretty small too and you don’t wonder how the can cause explosions when mixed and ignited.
Chemical explosions are weaker than nuclear ones, but that is not down to the size of the individual molecules and atoms.
The difference comes from the fact that chemical reactions make use of the electromagnetic forces that hold atoms together in molecules while nuclear reactions deal with nuclear forces that hold the atomic nucleus together. In both case you induce them to go from one state to another that require less energy to maintain and give up the extra energy. (And in the process help the same reaction happen in other parts nearby.)
The forces holding atoms together are much stronger than the one holding molecules together, so there is a lot more energy to be gained from splitting or merging atoms than from chemical reactions.
Splitting one atom of Uranium gives you a minuscule amount of energy: 3.2×10 ^-11 J. But, in one gram of uranium, there’s 2.56×10 ^26 atoms, so keep multiplying that by say 5-10kg (10^3 grams) of typical warhead and you get a lot of energy.
in a normal chemical reaction, the energy you get out is stored in the bond between the various atoms and molecules. the energy of electrons clinging onto much larger nuclei.
when you perform nuclear fission, you’re actually destroying matter. you end up with less material than when you started. that missing matter was converted, in its entirety, into energy. how much energy? *a lot* E=mc^2 is actually for calculating it.
to help understand. in SI units. energy is joules (1 joule will lift an apple 1 meter straight up), mass is in kilograms (a textbook is 1-2 kg), and C is *the speed of light* (about 300 *million* meters per second) which is then squared.
a nuclear weapon is somewhere north of 15 kgs of material that scientists and engineers are trying to fission as quickly and violently as possible.
Because that atom is made up of smaller particles that have the same charge, and same charges repel. So to bind them together, you need A LOT of energy. And when they do split, that energy is released.