Question

Which of the following options is applicable for the two isotopes of uranium, \[\ce{^235_92U}\] and \[\ce{^238_92U}\]?

Options

• \[\ce{^235_92U}\] is more easily fissionable than \[\ce{^238_92U}\].

• \[\ce{^235_92U}\] is fissionable by slow-moving neutrons only.

• \[\ce{^238_92U}\] is fissionable by fast-moving neutrons only.

• All of the above.

Answer 1

All of the above.

Explanation:

U-235 is highly fissionable and splits using slow (thermal) neutrons, whereas U-238 is stable and requires highly energetic, fast-moving neutrons to undergo fission.