What is the heaviest element in the periodic table?
Oganesson
Oganesson is expected to have an extremely broad polarizability, almost double that of radon.[4] By extrapolating from the other noble gases, it is expected that oganesson has a boiling point between 320 and 380 K.[4] This is very different from the previously estimated values of 263K[79] or 247 K.[80] Even given the large uncertainties of the calculations, it seems highly unlikely that oganesson would be a gas under standard conditions,[4] and as the liquid range of the other gases is very narrow, between 2 and 9 kelvins, this element should be solid at standard conditions. If oganesson forms a gas under standard conditions nevertheless, it would be one of the densest gaseous substances at standard conditions, even if it is monatomic like the other noble gases.