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White phosphorus, yellow phosphorus, or simply tetraphosphorus (P 4) is an allotrope of phosphorus. It is a translucent waxy solid that quickly yellows in light (due to its photochemical conversion into red phosphorus ), [ 2 ] and impure white phosphorus is for this reason called yellow phosphorus.
White phosphorus, yellow phosphorus or simply tetraphosphorus (P 4) exists as molecules of four phosphorus atoms in a tetrahedral structure, joined by six phosphorus—phosphorus single bonds. [1] The free P 4 molecule in the gas phase has a P-P bond length of r g = 2.1994(3) Å as was determined by gas electron diffraction . [ 2 ]
White phosphorus is reduced by sodium-potassium alloy: [6] P 4 + 12 Na → 4 Na 3 P. Phosphorus reacts with sodium in an autoclave at 150 °C for 5 hours to produce Na 3 P. [7] Alternatively the reaction can be conducted at normal pressures but using a temperatures gradient to generate nonvolatile Na x P phases (x < 3) that then react further ...
One exception is phosphorus, for which the most stable form at 1 bar is black phosphorus, but white phosphorus is chosen as the standard reference state for zero enthalpy of formation. [2] For example, the standard enthalpy of formation of carbon dioxide is the enthalpy of the following reaction under the above conditions:
15 P phosphorus (white) use (T/K) 279 307 342 388 453 549 CRC.c,e (T ... Valid results within the quoted ranges from most equations are included in the table for ...
People exposed to white phosphorus can suffer severe and sometimes deadly bone-deep burns. It can cause organs to shut down, and burns on just 10% of the body can be fatal, HRW said.
The acid is prepared industrially via a two step process: Firstly, elemental white phosphorus reacts with alkali and alkaline earth hydroxides to give an aqueous solution of hypophosphites: P 4 + 4 OH − + 4 H 2 O → 4 H 2 PO − 2 + 2 H 2. Any phosphites produced in this step can be selectively precipitated out by treatment with calcium salts.
The Pentagon recommended providing the white phosphorus shells to Ukraine as part of several aid packages, including a recent one, as a Presidential Drawdown Authority, according to the officials.