How many elements are gases at room temperature?

At standard room temperature, 11 elements are gases: hydrogen, nitrogen, oxygen, fluorine, chlorine, and the noble gases helium, neon, argon, krypton, xenon, and radon. The exact number can change depending on the temperature convention used, but 20°C is a common reference point. These gaseous elements are spread across the periodic table and are essential to life, the atmosphere, and industry. Oxygen and nitrogen dominate Earth’s air, while noble gases are present in smaller amounts. Fluorine and chlorine are highly reactive gases, unlike the inert noble gases.