Monoammonium phosphate or Ammonium dihydrogen phosphate or Mono Ammonium Phosphate, NH4•H2PO4, is formed when a solution of phosphoric acid is added to ammonia until the solution is distinctly acid. It crystallizes in quadratic prisms. It is often used in the blending of dry agricultural fertilizers. It supplies soil with the elements nitrogen and phosphorus in a form which is usable by plants. The compound is also a component of the ABC powder in some dry chemical fire extinguishers. This substance is also supplied in a jade green or aquamarine crystal growing box kit for kids.
Uses:
Monoammonium phosphate (MAP) or Mono ammonium phosphate is used as a fire-prevention agent for fabric, timber and paper, as well as a fire-prevention coating, and dry powder for fire extinguisher. For food grade the item is mainly used as a fermentation agent, nourishment, and so on. Used as a high effective non-chloride N, P compound fertilizer in agriculture. Its total nourishment (N=P2O5) is at 73%, and may be used as a basic raw material for N, P and K compound fertilizer.
Diammonium hydrogen phosphate, or diammonium phosphate, (NH4)2HPO4, is formed by evaporating a solution of phosphoric acid with excess of ammonia. It crystallizes in large transparent prisms, which melt on heating and decompose, leaving a residue of metaphosphoric acid, (HPO3).
Uses
Diammonium phosphate or Di ammonium phosphate DAP is used as a fertilizer and a fire retardant. When applied as plant food, it temporarily increases the soil pH (more basic), but over a long term the treated ground becomes more acidic than before upon nitrification of the ammonium. It is incompatible with alkaline chemicals because its ammonium ion is more likely to convert to ammonia in a high-pH environment. As a flame retardant, it lowers the combustion temperature of the material, decreases maximum weight loss rates, and causes an increase in the production of residue or char.
DAP is also used as a yeast nutrient in winemaking and brewing mead; as an additive in some brands of cigarettes purportedly as a nicotine enhancer; to prevent afterglow in matches, in purifying sugar; as a flux for soldering tin, copper, zinc and brass; and to control precipitation of alkali-soluble and acid-insoluble colloidal dyes on wool.