Dihydrogen phosphate potassium

In the KHPO4 structure, each PO4 tetrahedron is linked to four others via H bonds from each of its corners, to form a continuous three-dimensional anionic network throughout the crystal. In the tetragonal form, the O-H-0 bonds are short and all the P-0 bonds are of equivalent length and a tetragonal arrangement is formed about each P atom. 

When transition to the orthorhombic form occurs, this arrangement becomes slightly asymmetric (12.406). There is an ordering of the H atom positions which entails the production of electric dipoles associated with each PO4 tetrahedron. An applied electric field will orient these dipoles throughont the crystal, bnt on reversal of the field, a reversal of these dipoles is effected. 

FIGURE 12.50 Influence of H-bonding on electrical properties, (a) Ferroelectric KH2PO4, (b) antiferroelec-tric NH4H2PO4. Orthorhombic cells viewed down [c] axes. H bonds parallel to plane of paper. Numerals give heights of P atoms above c = ( ), cations yc above each PO4 tetrahedron. 

A whole series of salts MH2PO4 and MH2ASO4 are known, where M = K, NH4, Rb, Cs, Tl. Most of these are isomorphous with KH2PO4 and show piezoelectric, ferroelectric and other interesting properties. Deuterated salts such as KD2PO4 are also well characterised (Tables 12.52 and 12.53). 

The alkali metal hydrogen phosphates MH2PO4 can be obtained relatively easily as large ultra-pure crystals, although in other respects (e.g. water solubility) they leave much to be desired as practical ferroelectric materials (Tables 12.66 and 12.67). 

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Dissolve 680 mg potassium dihydrogen phosphate in 50 ml water and add 4.6 ml 0.1 M caustic soda then dilute 1+9 with water. 

The following procedure is described in U.S. Patent 2,837,464 from a solution of 3 grams of yeast extract (Difco) in 3.0 (iters of tap water containing 13.2 grams of potassium dihydrogen phosphate and 26.4 grams disodium hydrogen phosphate (pH of the solution, 6.9)... 

For many years such media have been based on strong salt solutions, e.g. calcium chloride brines. Sodium dichromate has been used (seep. 17 26), but recently other inhibitors have been claimed to be effective. One patent quotes N-alkyl-substituted alkanolamines, e.g. 2-ethyl ethanolamine -I- BTA at pH A mixture of hydrazine hydrochloride -i- BTA has been claimed as well as a mixture of gelatin -h triethanolamine -h potassium dihydrogen phosphate . Other examples are to be found in the patent literature and the above are quoted to illustrate the diversity of chemicals that may be used. 

Reagents. Standard phosphate solution. Dissolve 1.721 g potassium dihydrogen-phosphate (dried at 110 °C) in 1 L of water in a graduated flask. Pipette 10.0 mL of this solution into a 1 L graduated flask and dilute to the mark. The resulting dilute solution contains 0.01 mg phosphorus pentoxide per mL. 

C03-0067. Write chemical formulas for these compounds (a) sodium sulfate (b) potassium sulfide (c) potassium dihydrogen phosphate (d) cobalt(II) fluoride tetrahydrate (e) lead(IV) oxide (Q sodium hydrogen carbonate and (g) lithium perbromate. 

Fig. 5.4 Chromatogram of atenolol for column validation CRS which is supplied with theCRS. Asimilarchromatogram must be obtained to assure the suitability ofthe chromatographic system. (Column 4.6 x 150 mm Nucleosil C-18 [5 pm] Mobile phase 1.0 g sodium octane-sulphonate, 0.4gtetrabutyl ammonium hydroxide, 2.72 g potassium dihydrogen phosphate in 800 ml water [pH 3.0], 20 ml tetrahydrofuran and 180ml methanol, flowrate l.Oml/min and detection wavelength 226 nm).

Fig. 5.5 Chromatogram ofchlor-prothixene hydrochloride CRS which contains 2.7 % ofthe f -isomer. (Column 4 x 120 mm hypersil BDS [3 pm]. Mobile phase 6.0 g potassium dihydrogen phosphate, 2.9 g sodium lauryl sulphate, 9.0 g tetrabutylammonium bromide 550 ml water, 50 ml methanol and400 ml acetonitrile, flow rate 1.5 ml/min and detection wavelength 254 nm.)...

Potassium dihydrogen phosphate Phosphoric acid, monopotassium salt (9) (7778-77-0)... 

Tarr and Hibbert13 published the first detailed study of the formation of bacterial cellulose. A systematic series of experiments, conducted with a view to obtaining a culture medium which did not support visible growth of A. xylinum until a suitable source of carbon was added, indicated that a solution (pH 5.0) containing 0.1% asparagine, 0.5% potassium dihydrogen phosphate, 0.1% sodium chloride and 0.5% ethanol satisfied these requirements. Maximum polysaccharide formation oc-... 

Number of mEq of potassium phosphate in 10 mL of potassium dihydrogen phosphate can be calculated from ... 

A potassium phosphate solution contains 3.5 g of potassium dihydrogen phosphate (MW = 136) and 6.5 g of potassium monohydrogen phosphate (MW = 174) in 40 mL. If 5 mL of this solution are added to a liter of D5W, how many milliequivalents of potassium phosphate will be represented in the infusion ... 

It is considered that the direct method of preparing radioactive di-isopropyl phosphorofluoridate possesses advantages compared to the method of B. Witten and J. I. Miller, which starts with radioactive potassium dihydrogen phosphate.5... 

Currently used nonlinear optical crystals are potassium dihydrogen phosphate (KDP) and barium borate (BBO). Compared to KDP, the advantages of BBO are its transparency in the UV and its larger quantum efficiency of up-conversion by a factor of 4—6. For a given position of the crystal, only a narrow band of the fluorescence spectrum is up-converted. Therefore, if the full fluorescence spectrum is of interest, the crystal must be rotated at a series of angles. An example of experimental set-up is presented in Figure 11.2. The fwhm of the response is 210 fs. 

Cabon tetrachloride, n-hexane, chloroform, ACN, acetone, THF, pyridine, acetic acid, and their various mixtures were applied as mobile phases for adsorption TLC. Methanol, 1-propanol, ACN, acetone, THF, pyridine and dioxane served as organic modifiers for RP-TLC. Distilled water, buffers at various pH (solutions of and dipotassium hydrogen phosphate or potassium dihydrogen phosphate) and solutions of lithium chloride formed the aqueous phase. Carotenoids were extracted from a commercial paprika sample by acetone (lg paprika shaken with 3 ml of acetone for 30 min), the solution was spotted onto the plates. Development was carried out in a sandwich chamber in the dark and at ambient temperature. After development (15 cm for normal and 7cm for HPTLC plates) the plates were evaluated by a TLC scanner. The best separations were realized on impregnated diatomaceous earth stationary phases using water-acetone and water-THF-acetone mixtures as mobile phases. Some densitograms are shown in Fig.2.1. Calculations indicated that the selectivity of acetone and THF as organic modifiers in RP-TLC is different [14],... 

Figure 3.16 Chromatogram of hydantoins on polymethacrylate stationary phase. Conditions columns, Shodex RSPak DE613 (methacrylate gel) eluent, 1 1 mixture of 0.033 M disodium hydrogen phosphate and potassium dihydrogen phosphate flow rate, 2.0 ml min-1 detection, UV 210 nm temperature, 50 °C. Compounds 1, R = (CH2)2C02H 2, R = CH2OH 3, R = H 4, R = CH3 and 5, R = C2H5.

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