PPh 3 + CH 3 Br → CH 3 PPh + 3 Br − Phosphorus pentachloride and related halophosphonium compounds. Quaternary phosphonium cations (PR +4) are produced by alkylation of organophosphines. The formula PO43- means that this ion is composed of: one atom of phosphorus, four atoms of oxygen, and three extra electrons. Asked in Earth Sciences What is the ion name for phosphorus ? PO4 is phosphate. It does not occur naturally, but is manufactured from phosphate rocks. For example, the reaction of triphenylphosphine with methyl bromide gives methyltriphenylphosphonium bromide, the precursor to a Wittig reagent:. P 3- About 550 different minerals have been found to contain phosphorus, but, of these, the principal source of phosphorus is the apatite series in which calcium ions exist along with phosphate ions and variable amounts of fluoride, chloride, or hydroxide ions, according to the formula [Ca 10 (PO 4) … a phosphorus ion is just its elemental symbol and a charge. White phosphorus is a colorless, white, or yellow waxy solid with a garlic-like odor.