Question

30.2 28U is long-lived but ultimately unstable; it will eventually STOP TO THINK 30.2 spontaneously break into two fragments, a "He nucleus and a 234Th nucleus, in a process called alpha decay, which we'll learn about in the next section. A great deal of energy is released in the process. What must be true about the masses of the nuclei involved?

Answer 1

Option. (C) is correct option.

Because the mass of uranium is,

Mass(uranium)= 238.02891u

And mass of Thorium is,

Mass(Thorium)= 234.0436u

And mass of Helium is,

Mass(Helium)= 4.002602u.

When we will add the mass of Thorium and mass Helium. We will get 238.046202 u.

Which is more than mass of uranium.

Therefore,

Mass(Uranium) is less than sum of mass(thorium) and mass(Helium)