Calcium dihydrogen phosphate
Calcium dihydrogen phosphate (also called mono-calcium orthophosphate) Ca(H2PO4)2 is a chemical compound.
Decomposes at 203 °C. The common Ca(H2PO4)2•H2O releases a water molecule before it melts at 109 °C.
Phosphorus is an important nutrient and so is a common component of fertilizers. Phosphate rock, Ca3(PO4)2 is available but is too insoluble to be an efficient fertilizer. Therefore it is frequently converted into the more soluble calcium dihydrogen phosphate, generally by the use of sulfuric acid H2SO4, the result is hydrated to turn the calcium sulfate into the dihydrate gypsum and sold as "superphosphate of lime"
- Ca3(PO4)2 + 4 H2SO4 + 2 H2O → 2 CaSO4•2H2O + Ca(H2PO4)2•H2O
Alternately phospate rock may be treated with phosphoric acid to produce a purer form of calcium dihydrogen phosphate and is sold as "triple phosphate".
- Ca3(PO4)2 + 4 H3PO4 → 3 Ca(H2PO4)2
Monocalcium Phosphate is also used in the food industry as a Leavening agent to cause baked goods to rise. Since it is acidic in nature it provides the better balance towards the other common leavening agent Baking soda (Sodium Bicarbonate) that is alkalic in nature. This will be useful to adjust the pH of the final end product. Apart from acting as leavening agent, it also possess some microbial inhibition because of the phosphate ions present in the molecule.