Hydrogen, with the chemical formula H₂ and CAS number 1333-74-0, is the lightest and most abundant chemical element in the universe. It is a key component in many industries and has unique properties that make it valuable in a variety of applications. Here are some key characteristics of hydrogen:
Chemical and Physical Properties:
State at Room Temperature: Hydrogen is a colorless, odorless, and tasteless gas at standard conditions.
Boiling Point: -252.87°C (-423.17°F) at 1 atm.
Melting Point: -259.14°C (-434.45°F) at 1 atm.
Density: 0.0899 g/L at 0°C (32°F) and 1 atm, making it significantly lighter than air.
Solubility: Hydrogen is sparingly soluble in water and other solvents.
Reactivity:
Flammability: Hydrogen is highly flammable and reacts explosively with oxygen.
Energy Content: Hydrogen has a high energy content per unit mass, making it an attractive fuel source.
Reactivity with Metals and Nonmetals: Hydrogen can react with many elements to form hydrides.
Uses:
Ammonia Production: A significant portion of hydrogen is used in the Haber process for producing ammonia, which is then converted into fertilizers.
Refining Petroleum: Hydrogen is used in oil refineries for hydrocracking and hydrodesulfurization.
Rocket Fuel: Liquid hydrogen is used as a rocket propellant, often in combination with liquid oxygen.
Fuel Cells: Hydrogen is used in fuel cells to generate electricity without combustion.
Metal Working: Hydrogen is used in metal working for welding and cutting operations.
Food Industry: Hydrogen is used in the hydrogenation of oils to produce margarine and other products.