If the following element undergoes alpha decay, which element does it change into?

Question

234/90 Th

a
Uranium (U)
b
Francium (Fr)
c
Radium (Ra)
d
Radon (Rn)

Answer 1

Alpha decay involves the loss of an alpha particle, which is composed of 2 protons and 2 neutrons. When an element undergoes alpha decay, its atomic number decreases by 2 and its atomic mass decreases by 4.

For the element \(^{234}_{90}\text{Th}\) (Thorium):

• Atomic number decreases from 90 to 88.
• Atomic mass decreases from 234 to 230.

The new element will have an atomic number of 88, which corresponds to Radium (Ra).

So, the answer is: c. Radium (Ra)