Monocalcium phosphate

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Monocalcium phosphate
Calcium dihydrogen phosphate .png
Monocalcium phosphate spoon.JPG
Identifiers
CAS number 7758-23-8 YesY
PubChem 24454
Properties
Molecular formula CaH4P2O8
Molar mass 234.05 g/mol
Appearance white powder
Density 2.220 g/cm3
Melting point 109 °C
Boiling point 203 °C (decomposes)
Solubility in water 2 g/100 mL
Solubility soluble in HCl, nitric acid, acetic acid
Refractive index (nD) 1.5176
Structure
Crystal structure triclinic
Hazards
EU Index Not listed
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentine Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point Non-flammable
Related compounds
Other anions Calcium pyrophosphate
Other cations Magnesium phosphate
Dicalcium phosphate
Tricalcium phosphate
Strontium phosphate
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Monocalcium phosphate is a chemical compound with the formula Ca(H2PO4)2 ("ACMP" or "CMP-A" for anhydrous monocalcium phosphate). It is commonly found as the monohydrate (""MCP" or "MCP-M"), Ca(H2PO4)2·H2O (CAS# 10031-30-8). Both salts are colourless solid that are used mainly as a leavening agent.[1]

Preparation[edit]

It is produced by treating calcium oxide with phosphoric acid:

Ca(OH)2 + 2 H3PO4 → Ca(H2PO4)2 + 2 H2O

Use as leavening agent[edit]

Calcium dihydrogen phosphate is used in the food industry as a leavening agent, i.e., to cause baked goods to rise. Because it is acidic, when combined with an alkali ingredient, commonly sodium bicarbonate (baking soda) or potassium bicarbonate, it reacts to produce carbon dioxide and a salt. Outward pressure of the carbon dioxide gas causes the rising effect. When combined in a ready-made baking powder, the acid and alkali ingredients are included in the right proportions such that they will exactly neutralize each other and not significantly affect the overall pH of the product. ACMP and MCP are fast acting, releasing most carbon dioxide within minutes of mixing. It is popularly used in pancake mixes. In double acting baking powders, MCP is often combined with the slow acting acid sodium acid pyrophosphate (SAPP).[2]

See also[edit]

References[edit]

  1. ^ Klaus Schrödter, Gerhard Bettermann, Thomas Staffel, Friedrich Wahl, Thomas Klein, Thomas Hofmann "Phosphoric Acid and Phosphates" in Ullmann’s Encyclopedia of Industrial Chemistry 2008, Wiley-VCH, Weinheim. doi:10.1002/14356007.a19_465.pub3
  2. ^ John Brodie, John Godber "Bakery Processes, Chemical Leavening Agents" in Kirk-Othmer Encyclopedia of Chemical Technology 2001, John Wiley & Sons. doi:10.1002/0471238961.0308051303082114.a01.pub2

Further reading[edit]

  • Havlin, J.L., J.D. Beaton, S.L. Tisdale, and W.L. Nelson. 2005. Soil Fertility and Fertilizers. 7th edn. Pearson Prentice Hall, N.J., ISBN 0130278246