Question

The naturally occurring radioactive isotope 232Th does not make good fission fuel, because it has an even number of neutrons; however, it can be bred into a suitable fuel (much as 238U is bred into 239P).

a) True
b) False

Answer 1

The statement is false as 232Th can be used as a nuclear fuel by being bred into fissile uranium-233, similarly to how uranium-238 is bred into fissile plutonium-239.

Step-by-step explanation:

The statement regarding the natural radioactive isotope 232Th is false. Thorium-232 can indeed be used as a nuclear fuel, not because of its neutron count but because it is a fertile material that can be converted into a fissile isotope, such as uranium-233 (233U), through a process called breeding. This process is similar to how uranium-238 (238U) is bred into plutonium-239 (239Pu), which is also not found in nature and is highly fissile. The breeding process in both cases involves the absorption of a neutron by the fertile isotope (232Th or 238U), which becomes a new isotope and then decays into a fissile form (e.g., 233U or 239Pu) suitable for use in a nuclear reactor.

Plutonium-239 and uranium-233 have advantages as fission fuels over the naturally occurring uranium-235 (235U), as they can generate more neutrons per fission, and it is easier for thermal neutrons to induce fission in them.