Question

What do you understand by $_{92}U_{235}$ and $_{92}U_{238}$a

Answer 1

Both the isotopes of Uranium 235 and 238 are the different mass number where as 92 is only the atomic number for both the cases.

₉₂U²³⁵ is the isotopes of Uranium. Whose percentage quantity is less than that of ₉₂U²³⁸.

For the nuclear having less velocity are used but in case of ₉₂U²³⁸, neutrons having high velocity are used.