French Revolution Timeline May 5, 1789 A meeting of the Estates-General is called by Louis XVI in Versailles to discuss and approve a new tax plan. June 17, 1789 Three Poitevin cures decide to join the Third Estate, leaving the Chambers of the Clergy.
Helium is a chemical element with symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group in the periodic table. Its boiling and melting points are the lowest among all the elements.
Helium is an inert gas. The only gas with a lower reactivity is neon. This low reactivity makes helium a valuable gas to use in manufacturing and repair processes when an inert atmosphere is required. Helium also has the second-lowest density of any gas along with a very high thermal conductivity.