Он2, or H2, is a diatomic molecule consisting of two hydrogen atoms. It is the most abundant molecule in the universe and plays a crucial role in various chemical reactions, including those in stars. In its gaseous form, он2 is colorless, odorless, and highly flammable. It is commonly used in industrial applications, such as fuel cells and as a reducing agent in chemical processes. Additionally, он2 is essential for life, as it is a key component of water, which is vital for all known forms of life.