Rn^222, also known as Radon-222, is a radioactive isotope of radon. Let's delve into its nuclear composition in detail:

- The nucleus of Rn^222 contains 86 protons and 136 neutrons, giving it a total atomic mass of 222 atomic mass units.

- With 86 protons, Rn^222 belongs to the element radon on the periodic table. Protons are positively charged subatomic particles found in the nucleus.

- Rn^222 has 136 neutrons, which are neutral subatomic particles found in the nucleus along with protons. Neutrons help stabilize the nucleus of the atom.

- Being an isotope of radon, Rn^222 has the same number of protons as other radon isotopes but differs in the number of neutrons, resulting in its unique nuclear composition.

- Rn^222 is a radioactive isotope, meaning it undergoes radioactive decay by emitting alpha particles. This process transforms it into other elements over time.
In conclusion, the nuclear composition of Rn^222 consists of 86 protons and 136 neutrons in its nucleus, making it a distinctive and radioactive isotope of radon.