What Elements Are Gases At Room Temperature. Carbon dioxide, for example, is a gas at room temperature and atmospheric pressure, but becomes a liquid under sufficiently high pressure. Elements that are gases at room temperature are all nonmetals (such as he, ar, n2, o2, and so on).
Four other elements are liquids slightly warmer. Common gases at room temperature include both elements (such as h 2 and o 2) and compounds (such as co 2 and nh 3).; Elemental hydrogen (h, element 1), nitrogen (n, element 7), oxygen (o, element 8), fluorine (f, element 9), and chlorine.