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.
Learn about helium balloons, noble gases, the helium atom, the balloon boy hoax, space related helium storage tanks, how helium can change a personâs voice and much more with our range of interesting helium facts, properties and information. Helium is a chemical element with the symbol He and atomic number 2. Helium is a colorless, tasteless and odorless gas. Helium is the second most common element in the Universe (after hydrogen), making up around 24% of its mass. Helium is part of a group of chemical elements called noble gases, the other five that occur naturally are neon, argon, krypton, xenon and radon. Under normal conditions they share similar properties, including being less likely to participate in chemical reactions due to their outer shell of electrons being full.