Non-Hodgkin lymphoma is broadly divided into two major groups: B-cell lymphomas (which develop from abnormal B-lymphocytes, which is most common), and T-cell lymphomas (which develop from abnormal T-lymphocytes). Lymphocytes are a type of white blood cell that helps the body fight infections.
The atomic number of radon (Rn) is 86 and the atomic weight of Rn is 222 grams/mole.
The noble gases (arranged in order of increasing atomic weight) are helium, neon, argon, krypton, xenon and radon. Helium, neon and argon are the three noble gases with the lowest atomic masses. Helium, Neon, Argon. Helium, neon, and argon are the three lightest members of the noble  gases. Hydrogen is the lightest of all elements. According to the Periodic  Table, its atomic weight is 1.00794 u, even lighter than helium.