Which of the following is NOT a decay product of radon?

In the context of radon and its decay process, Francium-223 is not a decay product of radon. Radon-222, a noble gas, is part of the uranium decay series and undergoes a series of radioactive decays. In this series, radon decays into several isotopes, which include Lead-210 and Bismuth-214, both of which are recognized decay products.

Lead-210 is formed when radon-222 emits an alpha particle, leading to Lead-210, which then continues to decay further. Similarly, Bismuth-214 is another product that arises from the decay of Lead-214, which is in the decay chain following radon.

On the other hand, Radium-226 is an isotope that precedes radon in the decay series and ultimately decays into radon. Therefore, it is actually part of the process rather than a result of it.

Francium-223, however, does not appear in this decay chain related to radon. It has its own separate decay series stemming from different parent isotopes, and is thus not connected to the decay process of radon. This understanding highlights the complex nature of radioactive decay and the importance of accurately identifying the relationships