Question

How many neutrons in an `""^238U` atom?

Answer 1

In `""^238U`........?

Explanation:

Well, for a start, the number of nuclear protons is `92`; i.e. for uranium, `Z,"the atomic number"=92` this is what defines uranium as an element.

Now the mass number is `238`, and therefore there are `238-92=146* "neutrons"`.

And finally the number of electrons, which is easy given what we know. We know we deal with a NEUTRAL element, and if `Z=92`, the positive charge provided by the protons must be matched by an equal number of electrons, conceived to whizz around the nuclear core; i.e. there are 92 electrons..... The fissile isotope of uranium is `""^235U`; how many neutrons in this nuclide?