Chapter 16, Problem 10RQ

When an element like thorium decays, does it become a completely different element or a version of thorium?

To determine

Whether the thorium becomes a completely different element or a version of thorium when it decays.

Answer to Problem 10RQ

The thorium becomes protactinium, a completely different element when it decays.

Explanation of Solution

The transformation of an unstable radioactive element into another element is termed as transmutation. Many elements transmute and release energy. In the transmutation of uranium, thorium, gamma rays and an alpha particle are found.

The element thorium-234 is also a radioactive element with the atomic number 90, and whenever the process of decay occurs, it emits a beta particle. Due to the emission of a beta particle, a neutron of the thorium becomes a proton and its atomic number increases by 1. And thorium becomes a new element with the atomic number 91 that is known as protactinium.

Conclusion:

Therefore, the thorium becomes protactinium, a completely different element when it decays.