Ammonia

—A colorle gas with a characteristic pungent odor (hartshorn), and a marked alkaline taste. It has a specific gravity of 8.5 (hydrogen being 1) and is lighter than air. It burns in oxygen, producing water and nitrogen, and is a powerful base, combining with all acids to form salts. Ammonia is easily liquefied at ordinary temperatures, a pre ure of seven atmospheres being sufficient; it is also the most soluble of gases, one volume of water di olving over 800 volumes of it at ordinary temperature.