which element is a highly flammable gas that is the lightest and most abundant gas in the universe?
A colorless , highly flammable element , that occurs as a diatomic molecule , H2 , the lightest of all gases and the most abundant element in the universe , used in the production of synthetic ammonia and methanol , in petroleum refining , in the hydrogenation of organic materials , as a reducing atmosphere , in oxyhydrogen torches , in cryogenic ...