Ammonia
Ammonia acts as refrigerant gas, and feedstock for a wide variety of other chemicals.
At room temperature and atmospheric pressure, ammonia is a pungent, colorless gas. It may be compressed and cooled to a colorless liquid. Liquid ammonia is lighter than water. Ammonia is a highly reactive chemical.
Ammonia is utilized extensively in the fertilizer industry produce solid material such as ammonium salts, nitrate salts, and urea. Used in both absorption and compression systems, ammonia is the oldest, most efficient and economical mechanical refrigerant known. Ammonia or dissociated ammonia is used in such metal treating operations as nitriding, carbo-nitriding, bright annealing, furnace brazing, sintering and other application where protective atmosphere are required).