Answer:
157 64 Gd + 1 0 n -----> 158 64 Gd + γ
Step-by-step explanation:
In a nuclear reaction, both mass and charge are conserved. If we look at the equation above, we will notice that this principle was followed.
Gama rays has no mass and charge because it is an electromagnetic wave. The relative atomic mass of the isotope of Gd formed in the reaction is 158 Gd. The atomic number remains the same.