Dihydrogen phosphate or dihydrogenphosphate ion is an

inorganic ion In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemis ...

with the formula ₂PO₄sup>−. Phosphates occur widely in

natural Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are p ...

systems. These sodium phosphates are artificially used in food processing and packaging as emulsifying agents, neutralizing agents, surface-activating agents, and leavening agents providing humans with benefits. Emulsifying agents prevent separation of two ingredients in processed foods that would separate under natural conditions while neutralizing agents make processed foods taste fresher longer and lead to an increased shelf-life of these foods. Surface-activating agents prevent surface-tension formation on liquid-containing processed foods and finally, leavening agents are used in processed foods to aid in the expansion of yeast in baked goods. Dihydrogen phosphate is employed in the production of pharmaceuticals furthering their importance to medical practitioners of

gastroenterology Gastroenterology (from the Greek gastḗr- “belly”, -énteron “intestine”, and -logía "study of") is the branch of medicine focused on the digestive system and its disorders. The digestive system consists of the gastrointestinal tract ...

and humans in general. In this medical discipline, sodium phosphates are used as natural laxatives. Other medical applications include using sodium and potassium phosphates along with other medications to increase their therapeutic effects. Inflammation, certain cancers, and ulcers can benefit from the use of combination therapy with sodium and potassium phosphates. Potassium dihydrogen phosphate, the potassium salt, is useful to human in the form of pesticides. Potassium dihydrogen phosphate is a fungicide that is used to prevent powdery mildew on many fruits. Fruits that can benefit from the addition of potassium dihydrogen phosphate includes common fruits, peppers, and roses.

Structure

The dihydrogen phosphate anion consists of a central

phosphorus Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...

atom Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, and ...

surrounded by 2 equivalent

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

atoms and 2

hydroxy group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...

s in a

tetrahedral In geometry, a tetrahedron (plural: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular faces, six straight edges, and four vertex corners. The tetrahedron is the simplest of all the o ...

arrangement. Dihydrogen phosphate can be identified as an anion, an ion with an overall negative charge, with dihydrogen phosphates being a negative 1 charge. Dihydrogen phosphate contains 4 H bond acceptors and 2 H bond donors, and has 0 rotatable bonds.

Acid-base equilibria

Dihydrogen phosphate is an intermediate in the multi-step conversion of the polyprotic

phosphoric acid Phosphoric acid (orthophosphoric acid, monophosphoric acid or phosphoric(V) acid) is a colorless, odorless phosphorus-containing solid, and inorganic compound with the chemical formula . It is commonly encountered as an 85% aqueous solution, w ...

phosphate In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid . The phosphate or orthophosphate ion is derived from phospho ...

: This multistep conversion exemplifies that the dihydrogen phosphate ion is the conjugate base to phosphoric acid, while also acting as the conjugate acid to the phosphate ion. This means that dihydrogen phosphate can be both a hydrogen donor and acceptor.

Examples

Ammonium dihydrogen phosphate Ammonium dihydrogen phosphate (ADP), also known as monoammonium phosphate (MAP) is a chemical compound with the chemical formula (NH4)(H2PO4). ADP is a major ingredient of agricultural fertilizers and some fire extinguishers. It also has sign ...

((NH₄)(H₂PO₄)) *

Monocalcium phosphate Monocalcium phosphate is an inorganic compound with the chemical formula Ca(H2PO4)2 ("AMCP" or "CMP-A" for anhydrous monocalcium phosphate). It is commonly found as the monohydrate ("MCP" or "MCP-M"), Ca(H2PO4)2·H2O. Both salts are colourless sol ...

(Ca(H₂PO₄)₂)

Safety

Many foods including milk, eggs, poultry, and nuts contain these sodium phosphates.

Notes

References

{{Reflist Anions Phosphates