The fission of plutonium nuclei typically occurs when the nucleus is bombarded with slow neutrons (also called thermal neutrons). These neutrons have a lower energy and are more likely to be captured by the plutonium nucleus, causing it to become unstable and undergo fission.
- Fast neutrons have high energy, and while they can cause fission, they are less effective than slow neutrons.
- Slow neutrons are effective in initiating fission reactions in heavy nuclei such as plutonium-239.
- Deuterons and alpha particles are not typically involved in fission reactions with plutonium nuclei.
Thus, the correct answer is:
B)Slowneutrons Quick Tip: Plutonium undergoes fission when it captures slow (thermal) neutrons, which cause the nucleus to split. Fast neutrons are less likely to cause fission and require moderation to become effective.