Evaluation Methods. Several studies from around the world that have evaluated Incredible Years components meet the Promising Practices Network (PPN) criteria and have found Incredible Years to be a promising or proven program. These studies are listed below, by the component that was tested in the study.
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.
Neon is a colorless, odorless inert (not chemically reactive) gas. It is in a group called 'noble gases' in the periodic table. Neon has about two-thirds the density of air and is the second lightest noble gas after helium. Neon was discovered by British chemists Sir William Ramsay and Morris W. Travers in 1898.