7789-79-9

Basic information

• Product Name: Calcium hypophosphite
• Synonyms: CALCIUM HYPOPHOSPHITE;CALCIUM PHOSPHINATE;CALCIUM HYPOPHOSPHITE EXTRA PURE, DAC;Lime hypophosphite;CALCIUM HYPOPHOSPHITE TECHNICAL;CALCIUMHYPOPHOSPHITE,PURIFIED;Calcium hydrophosphite;Calcium bisphosphinate
• CAS NO: 7789-79-9
• Molecular Formula: Ca*2H₂O₂P
• Molecular Weight: 166.02
• EINECS: 232-190-8
• Product Categories: Inorganics
• Mol File: 7789-79-9.mol
• Article Data: 0

Chemical Properties

• Melting Point: decomposes [ALF93]
• Boiling Point: 480℃[at 101 325 Pa]
• Appearance: /white monoclinic crystals
• Density: 2.243[at 20℃]
• PKA: 12.6[at 20 ℃]
• Water Solubility: Soluble in water. Practically insoluble in alcohol. Slightly soluble in glycerol
• Sensitive: Hygroscopic
• Merck: 14,1675
• CAS DataBase Reference: Calcium hypophosphite(CAS DataBase Reference)
• NIST Chemistry Reference: Calcium hypophosphite(7789-79-9)
• EPA Substance Registry System: Calcium hypophosphite(7789-79-9)

Safety Data

• Hazard Codes: F
• Statements: 11
• Safety Statements: 7-15
• RIDADR: UN 3180 4.1/PG 2
• WGK Germany: 3
• TSCA: Yes
• HazardClass: 4.1
• Hazardous Substances Data: 7789-79-9(Hazardous Substances Data)

Usage

Description

Calcium hypophosphite has the molecular formula of Ca(H2PO2)2 and the molecular weight of 170.0631 g/mol. This salt can be prepared by the aqueous reaction of the carbonate or oxide with H3PO2: CaO + 2H3PO2 ? Ca(H2PO2)2 The salt is soluble in water (20 g/100 ml at 20°C) so that the solution must be evaporated to obtain crystals. Ca(H2PO2)2 has the CAS number of 7789-79-9 and the density of 1.59 g/cm3. It is composed of white square monoclinic crystalswhich are water soluble. It is insoluble in alcohol or ether.When heated to about 305°C, it disproportionates, forming calcium phosphate and phosphine: Ca(H2PO2)2 + heat ? CaHPO3 + PH3

Chemical Properties

white monoclinic, prismatic crystal(s) or granular powder(s); used as a corrosion inhibitor and in medicine [MER06] [HAW93]

Physical properties

Calcium hypophosphite is relatively soluble in water, and when added to a solution of sodium hypophosphite, forms a double salt. Crystals were obtained by slow evaporation of the solution to form dodecahedra with well-developed {110} faces. The crystal structure of CaNa(H2PO2)3 belongs to the cubic system with space group, P213, Z = 4 and a = 9.721?. The structure consists of two kinds of octahedral groups, one with a calcium atom and the other with a sodium atom. Each atom of the hypophosphite ions is coordinated to each one of the calcium and sodium atoms to form the octahedral. This structure is, in general, typical of the salts of hypophosphorous acid. Calcium hypophosphite is readily available commercially since its main usage, both industrially and in Research, has proven to be as a source of hypophosphite anions to form other hypophosphites.

Uses

Different sources of media describe the Uses of 7789-79-9 differently. You can refer to the following data:
1. It is employed as dietary supplement. The product is used as a flame retardant and applied to chemical plating. Moreover, the product is used as a food additive and an animal nutrition agent, applied to the manufacture of pharmaceutical products, as well as antioxidant and analytical reagent.
2. As corrosion inhibitor; in nickel plating. Pharmaceutic aid (retards oxidation of ferrous salts).

Flammability and Explosibility

Highlyflammable

InChI:InChI=1/Ca.HO2P/c;1-3-2/h;(H,1,2)/q+2;/p-1

Synthetic route

phosphorus + water (7732-18-5) + calcium oxide → calcium bis(hypophosphite) (7789-79-9)

Conditions	Yield
In water byproducts: PH3; addn. of 600 ml H2O to 120 g CaO, addn. of 20 g crushed, yellow P at boiling heat, boiling for 8-10 hours with replacement of vaporized H2O; introduction of CO2 into filtrate at 70-80°C; filtration after short boiling; vaporization till crystn.;; recrystn. from 3-4 parts H2O; yield 18-22 g pure Ca(PH2O2)2;;
In water byproducts: PH3; addn. of 600 ml H2O to 120 g CaO, addn. of 20 g crushed, yellow P at boiling heat, boiling for 8-10 hours with replacement of vaporized H2O; introduction of CO2 into filtrate at 70-80°C; filtration after short boiling; vaporization till crystn.;; recrystn. from 3-4 parts H2O; yield 18-22 g pure Ca(PH2O2)2;;

calcium phosphide + water (7732-18-5) → calcium bis(hypophosphite) (7789-79-9)

Conditions	Yield
With Ca2P2O7 In water decompn. of phosphorus lime with boiling water;; treatment of filtrate with CO2, crystn., drying at 100°C;;
With Ca2P2O7 In water decompn. of phosphorus lime with boiling water;; treatment of filtrate with CO2, crystn., drying at 100°C;;
In water

phosphorus + calcium hydroxide → calcium bis(hypophosphite) (7789-79-9)

Conditions	Yield
In chloroform; water byproducts: PH3; stirring on slight warming (ground temp. 44°C, surface temp. 37°C) for ca 80 hours; after storage for 24 hours decantation of clear layer, saturating with CO2, filtration;; vaporization in vac.;;
In calcium hydroxide byproducts: PH3; addn. of small amt. of yellow P to boiling lime milk, till there is no formation of PH3;; removal of excessive Ca(OH)2 by introduction of CO2 at elevated temp. into filtrate; vaporization on air or over H2SO4 in vac.;;
In water byproducts: PH3; aq. Ca(OH)2 suspension; in closed vessel;;

phosphorus (12185-10-3) → tricalcium diphosphate + calcium bis(hypophosphite) (7789-79-9) + phosphan (7803-51-2)

Conditions	Yield
With calcium hydroxide In neat (no solvent) byproducts: H2; on boiling water bath;

phosphorus (12185-10-3) → calcium bis(hypophosphite) (7789-79-9) + phosphan (7803-51-2)

Conditions	Yield
With calcium hydroxide In not given byproducts: H2; by heating;

calcium bis(hypophosphite) (7789-79-9) + calcium(II) nitrate (13477-34-4) → dicalcium phosphate anhydrous

Conditions	Yield
Stage #1: calcium bis(hypophosphite); calcium(II) nitrate In water Stage #2: at 200 - 252℃; under 33098.3 Torr; for 0.733333h;

calcium bis(hypophosphite) (7789-79-9) + bromine (7726-95-6) → hydrogen bromide (10035-10-6, 12258-64-9)

Conditions	Yield
With water without warming;

calcium bis(hypophosphite) (7789-79-9) + nickel dichloride → nickel (7440-02-0)

Conditions	Yield
With Na acetate In not given pH=5.0-5.5 (NaOH) , 92-93°C;

ammonium carbonate + calcium bis(hypophosphite) (7789-79-9) → ammonium phosphinate (7803-65-8)

Conditions	Yield
filtration, recrystn. from water or alc.;

calcium bis(hypophosphite) (7789-79-9) + copper(II) ion + urea (57-13-6) → poly(copper(II)-di-μ-hypophosphito-μ-urea)

Conditions	Yield
In water Cu(II) : Ca(H2PO2)2 : (NH2)2CO = 1:1:2; evapn. of the soln. for several d at room temp.; elem. anal.;

calcium bis(hypophosphite) (7789-79-9) + gold(III) → gold (7440-57-5, 457905-15-6)

Conditions	Yield
In water

calcium bis(hypophosphite) (7789-79-9) + calcium chloride + magnesium chloride (7786-30-3) → hydrogenchloride (7647-01-0) + magnesium hydrogen phosphate

Conditions	Yield
In hydrogenchloride byproducts: CaCl2; introduction of a hydrochloric solution of Ca(H2PO4)2 in boiling aq. MgCl2;;

calcium bis(hypophosphite) (7789-79-9) + lead hypophosphite → Pb(2+)*H2PO2(1-)*NO3(1-)=PbH2PO2NO3

Conditions	Yield
filtration and evapn. of filtrate; product contaminated with Ca;
filtration and evapn. of filtrate; product contaminated with Ca;

magnesium(II) nitrate (13446-18-9) + calcium bis(hypophosphite) (7789-79-9) → magnesium hydrogen phosphate

Conditions	Yield
In nitric acid introduction of a nitric solution of Ca(H2PO4)2 in boiling aq. Mg(NO3)2;;
In nitric acid aq. HNO3; introduction of a nitric solution of Ca(H2PO4)2 in boiling aq. Mg(NO3)2;;

calcium bis(hypophosphite) (7789-79-9) + oxalic acid (144-62-7) → hypophosphorous acid (6303-21-5)

Conditions	Yield
In water byproducts: Ca-oxalate; addn. of a soln. of oxalic acid to a soln. of Ca(H2PO2)2; pptn. in coldness;; removal of Ca-oxalate impurities by heating at 100 °C, standing for 5 days and by repeated filtration;;
In water byproducts: H3PO4, H3PO3; addn. of a hot soln. of 2 mol H2C2O4 in 100 ml H2O to a hot soln. of 2 mol Ca(H2PO2)2 in 2500 ml H2O (stirring); cooling, filtration, concentrating to a volume of 384 ml in a flow of N2 at 45 °C under reduced pressure;; content: 52 % H3PO2, less than 0.1 % H3PO3 and H3PO4;;

calcium bis(hypophosphite) (7789-79-9) + sodium carbonate (497-19-8) → sodium hypophosphite monohydrate (10039-56-2)

Conditions	Yield
In ethanol Ca(H2PO2)2 decompd. with Na2CO3 and alcoholic soln. evapd.;;
In ethanol Ca(H2PO2)2 decompd. with Na2CO3 and alcoholic soln. evapd.;;

calcium bis(hypophosphite) (7789-79-9) + cadmium(II) oxalate (814-88-0) → phosphan (7803-51-2)

Conditions	Yield
In water byproducts: cadmium calcium phosphinite;; boiling an excess of Cd-oxalate with Ca-phosphinite in water; formation of crystals of cadmium calcium phosphinite by evaporation of the filtrate;; cadmium calcium phosphinite was not isolated; decomposition on heating under evolution of PH3;;
In water byproducts: cadmium calcium phosphinite;; boiling an excess of Cd-oxalate with Ca-phosphinite in water; formation of crystals of cadmium calcium phosphinite by evaporation of the filtrate;; cadmium calcium phosphinite was not isolated; decomposition on heating under evolution of PH3;;

calcium bis(hypophosphite) (7789-79-9) + sodium carbonate decahydrate → sodium hypophosphite monohydrate (10039-56-2)

Conditions	Yield
In water byproducts: CaCO3; addn. of 50g Ca(H2PO2)2 in 150ml H2O to a boiling soln. of 42g Na2CO3*10H2O in 100ml H2O, pptn. of CaCO3, filtration, evapn. of filtrate;;
In water byproducts: CaCO3; addn. of 50g Ca(H2PO2)2 in 150ml H2O to a boiling soln. of 42g Na2CO3*10H2O in 100ml H2O, pptn. of CaCO3, filtration, evapn. of filtrate;;

ammonium sulfate + calcium bis(hypophosphite) (7789-79-9) → ammonium phosphinate (7803-65-8)

calcium bis(hypophosphite) (7789-79-9) → water (7732-18-5) + phosphan (7803-51-2)

Conditions	Yield
In neat (no solvent) byproducts: P, calcium phosphate; calcination in retort; first small amt. of H2O and PH3, later sublimation of small amt. of P with formation of calcium phosphate;;
In neat (no solvent) byproducts: P, calcium phosphate; calcination in retort; first small amt. of H2O and PH3, later sublimation of small amt. of P with formation of calcium phosphate;;

calcium bis(hypophosphite) (7789-79-9) → calcium phosphonate + phosphonic Acid (13598-36-2)

Conditions	Yield
With sulfur dioxide In not given in acidic soln.;
With SO2 In not given in acidic soln.;

calcium bis(hypophosphite) (7789-79-9) → calcium pyrophosphate + calcium metaphosphate + phosphorous

Conditions	Yield
With hydrogen In neat (no solvent) heating in H2;;
With H2 In neat (no solvent) heating in H2;;

calcium bis(hypophosphite) (7789-79-9) → hydrogen (1333-74-0) + phosphan (7803-51-2)

Conditions	Yield
In neat (no solvent) decompn. by heating over 300°C;;
In neat (no solvent) decompn. by heating over 300°C;;

calcium bis(hypophosphite) (7789-79-9) → calcium sulfite (752190-89-9)

Conditions	Yield
With sulfur dioxide In not given in neutral soln.;
With SO2 In not given in neutral soln.;

calcium bis(hypophosphite) (7789-79-9) + magnesium(II) oxalate (547-66-0, 879683-44-0) → magnesium hypophosphite * 6 H2O

Conditions	Yield
In not given boiling a solution of Ca(H2PO2)2 with an excess of a solution of Mg-oxalate; evaporation of the filtrate;;
In not given boiling a solution of Ca(H2PO2)2 with an excess of a solution of Mg-oxalate; evaporation of the filtrate;;

calcium bis(hypophosphite) (7789-79-9) + lithium oxalate (553-91-3) → lithium dihydrogenphosphate (14832-79-2)

Conditions	Yield
In water reaction of aq. soln. of Li2C2O4 and Ca(H2PO2)2 at 283-293 K;

cobalt(II) sulfate + calcium bis(hypophosphite) (7789-79-9) → hexaaquacobalt(II) bis(hypophosphite)

Conditions	Yield
In water slow evapn. aq. soln. of Co(II) hypophosphite, prepared by adding Ca(H2PO2)2 to CoSO4 (H2O);; mixt. filtered; crystals grown at 293 K in air;

Upstream product

• 7732-18-5 water 
• 12185-10-3 phosphorus 

Downstream Products

• 10035-10-6 hydrogen bromide 
• 7440-02-0 nickel 
• 7803-65-8 ammonium phosphinate 
• 7440-57-5 gold 
• 7647-01-0 hydrogenchloride 
• 10039-56-2 sodium hypophosphite monohydrate 
• 7732-18-5 water 
• 7803-51-2 phosphan 
• 13598-36-2 phosphonic Acid 
• 1333-74-0 hydrogen 
• 6303-21-5 hypophosphorous acid