what class of elements includes all of the elements that are gases at room temperature?
Elements can be solid, liquid, or gas at room temperature. Some periodic tables show this by use of a color code or other key. Neon is a gas at room temperature. Neon belongs to a family of elements that are all gases at room temperature. They are referred to as the noble gas family. There are eleven elements that are gaseous at room temperature. They include: hydrogen, helium, nitrogen, oxygen, fluorine, neon, chlorine, argon, krypton, xenon and radon. There are three elements that are liquids at room temperature and they include mercury, gallium, and bromine. The rest of the natural elements (76) are solid at room temperature.