Nitrogen is the most popular industrial gas, used in the following industries: *chemicals *pharmaceuticals *petroleum processing* glass and ceramic manufacture *steelmaking *pulp and paper *healthcare. Nitrogen may be referred to as LN (liquid nitrogen) in its liquid form. Bulk liquid nitrogen or cylinders of high pressure nitrogen are preferred for applications where purity is valued over cost and convenience. Gaseous nitrogen is used to shield potentially reactive materials from contact with oxygen. Nitrogen is colorless, odorless, nonflammable and tasteless. It gas is slightly lighter than air and soluble in water. While often used as an inert gas, nitrogen is not truly inert. It can be mixed with oxygen to form nitric oxide and nitrogen dioxide; mixed with hydrogen to form ammonia; or mixed with sulfur to form nitrogen sulfide. At a certain temperature, nitrogen will combine with active metals such as lithium, magnesium or titanium to form nitrides. Compounds formed with halogens and other organic compounds can be explosive. Nitrogen condenses at its boiling point, -195.8 degrees C (-320.4 degrees F), to a colorless liquid that is lighter than water.