Which type or types of nuclear reactors have thesecharacteristics?(a) Can use natural uranium as a fuel(b) Does not use a moderator(c) Can be refueled without shutting down

In a chemical reaction; the substance which involves in conversion is said to be reactant whereas the newly formed substance is called as product. Both reactant and products must be separated by arrow.

A nuclear reaction involves the conversion of nucleus with the emission of certain nuclei or small particles like alpha particles, beta particles, gamma rays etc.

Nuclear reactors are the reactors which produces energy with the help of nuclear reaction. The nuclear energy is the energy that is produces due to nuclear reactions between different radioactive nuclei and active particles like neutrons.