An atomic nucleus that can undergo fission when struck by a neutron is described as what?

An atomic nucleus that can undergo fission when struck by a neutron is described as what?

• A. Fertile
• B. Fissile
• C. Stable
• D. Radioactive

Answer: (B)

Fissile describes a nucleus that can undergo fission after absorbing a neutron and can sustain a chain reaction because the fission often releases neutrons that go on to cause more fissions. This makes materials like uranium-235 and plutonium-239 capable of fueling reactors or weapons. Fertile refers to materials that aren’t easily fissioned themselves but can capture a neutron and become fissile later (for example, uranium-238 becoming plutonium-239). Stable means it won’t decay, which is a separate concept from fission behavior, and radioactive means it is unstable and decays over time, again a different property.

Fissile describes a nucleus that can undergo fission after absorbing a neutron and can sustain a chain reaction because the fission often releases neutrons that go on to cause more fissions. This makes materials like uranium-235 and plutonium-239 capable of fueling reactors or weapons.

Fertile refers to materials that aren’t easily fissioned themselves but can capture a neutron and become fissile later (for example, uranium-238 becoming plutonium-239). Stable means it won’t decay, which is a separate concept from fission behavior, and radioactive means it is unstable and decays over time, again a different property.