Question

The most abundant isotope of uranium,238U , does not undergo fission. In a breeder reactor, however, a 238U atom captures a neutron and emits two beta particles to make a fissionable isotope of plutonium, which can then be used as fuel in a nuclear reactor.Write the balanced nuclear equation.

Express your answer as a nuclear equation

Answer 1

Number before symbol = atomic number.
Number after symbol = mass number.

92U238 + on1= ?Xy + -1eo + -1eo
The atomic number (charge) must add up on both sides and the mass number must add up on both sides.
Therefore, 92 + 0 on the left must equal to ? + (-1) + (-1) on the right
? must be 92+1+1 = 94
y must be 238 + 1 on the left = y + 0 + 0; solve for y = 239
The element X then is the element with atomic number 94 which is Pu.
So ?Xy can be replaced with 94Pu239.