Answer to Question #154427 in Inorganic Chemistry for Ukeme

Question

Which period has many elements with an unknown state in the periodic table?

Answer 1

Period 7

The period 7 elements are at the end of the periodic table and have only ever existed on Earth for tiny fractions of a second in particle accelerators. Certainly they never existed in enough quantities to form bonds with one another and start behaving as solids, liquids or gases. Although, they are sometimes called gases, but that's incorrect because heavy elements like that certainly wouldn’t be gases in normal circumstances.