Ammonium carbonate is an inorganic ammonium salt with the formula (NH4)2CO3. It appears as a white crystalline powder with a strong ammonia odor and is commonly known as baker's ammonia or hartshorn. It serves as a leavening agent in baking, especially for thin, crisp cookies and crackers, decomposing upon heating above 58°C to release ammonia, water, and carbon dioxide gases that cause dough to rise without leaving alkaline residues. Industrially, it is used in dye manufacturing, pharmaceuticals, and smelling salts. Chemically unstable, it decomposes in hot water and is prepared by reacting ammonia gas with carbon dioxide in aqueous solution. It is highly soluble in cold water but only slightly soluble in alcohol and insoluble in fats or oils. Due to its volatility and ammonia release, it requires careful handling in food applications to avoid off-flavors.