Question

before the fission process takes place, lead - 207 is bombarded with neutrons, it can change into
a bismuth - 208
b lead - 206
c lead - 208
d tellurium - 208

Explanation:

Step1: Understand neutron - capture reaction

When lead - 207 ($_{82}^{207}Pb$) is bombarded with neutrons ($_{0}^{1}n$), a neutron - capture reaction occurs. The atomic number remains the same (since neutrons have no charge), and the mass number increases by 1.
The reaction is $_{82}^{207}Pb+_{0}^{1}n
ightarrow_{82}^{208}Pb$.

Answer:

C. lead - 208