Question

What are some of the reasons that plutonium rather than uranium is used in all fission bombs and as the trigger in all fusion bombs?

a) Plutonium undergoes fission more readily
b) Plutonium is easier to produce
c) Plutonium has a lower critical mass
d) All of the above

Answer 1

Plutonium is favored in nuclear weapons because it is easier to fission with neutrons, requires a smaller critical mass, and produces more neutrons per fission, making it more efficient and easier to produce than uranium for these purposes.

Step-by-step explanation:

Plutonium is used rather than uranium in all fission bombs and as the trigger in fusion bombs for several reasons. Plutonium-239 is easier to fission with neutrons, making it a superior fission material, especially since it requires a smaller critical mass compared to uranium. Additionally, plutonium has a particularly small critical mass, which is advantageous for nuclear weapons. Plutonium also produces more neutrons per fission on average and is more chemically separable from uranium ore, making it easier to produce. While uranium bombs were developed, the relatively slow buildup of the uranium chain reaction allows for simpler devices to hold the critical mass together.