Which is not a fissionable material? — Nuclear Chemistry and Radioactivity Chemistry Question

💡 Solution & Explanation

$\text{U}^{235}$, $\text{U}^{233}$, and $\text{Pu}^{239}$ are highly fissile materials that can readily undergo fission when hit by slow (thermal) neutrons. $\text{U}^{238}$ is fertile; it does not easily undergo fission with slow neutrons but rather absorbs them to eventually form $\text{Pu}^{239}$. Therefore, correct answer is A.