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White phosphorus is the first allotrope of phosphorus, and in fact the first elementary substance to be discovered that was not known since ancient times. [3] It glows greenish in the dark (when exposed to oxygen) and is highly flammable and pyrophoric (self-igniting) upon contact with air.
Phosphorus condenses to a liquid below about 280°C and then solidifies (to the white phosphorus allotrope) below about 44°C (depending on purity). This same essential reaction is still used today (but with mined phosphate ores, coke for carbon, and electric furnaces). Brand's process yielded far less phosphorus than it could have.
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 Earth. It has an occurrence in the Earth's crust of about 0.1%, generally occurring as phosphate in minerals.
It can cause “excruciating burns and lifelong suffering,” a Human Rights Watch spokesperson said.
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 ]
While the cause was linked to the use of white phosphorus within 5 years, it took almost a century of strikes, bans, and taxes to stop its use in the industry. Image credits: Flares117
White phosphorus is controversial because of its ability to cause severe harm to civilian populations, according to HRW. When the substance ignites, it produces an intense heat of 1,500 degrees ...
Following the ideas laid out by the French chemist Charles Sauria, who in 1830 invented the first phosphorus-based match by replacing the antimony sulfide in Walker's matches with white phosphorus, matches were first patented in the United States in 1836, in Massachusetts, being smaller in size and safer to use. White phosphorus was later ...