Đốt cháy hoàn toàn 6,2 g phosphorus (P), thu được khối lượng oxide P2O5 là A. 14,2 g.    B. 28,4 g. C. 11,0 g.    D. 22,0 g. Lời giải rõ ràng dùm mik nha <3

The oxidation state of oxygen is -2, and for neutral molecules, the sum of the oxidation states is zero. In the case of P2O5, we can determine the oxidation state of phosphorus by setting up an equation: Let x be the oxidation state of P. So, 2x + 5(-2) = 0 2x - 10 = 0 2x = 10 x = +5 Therefore, the oxidation state of phosphorus in P2O5 is +5. Now, to find the mass of P2O5 produced from burning 6.2g of phosphorus: 1 mol of P reacts with 5 mol of O to produce 1 mol of P2O5. The molar mass of P is approximately 31g/mol and that of O is approximately 16g/mol. So, using stoichiometry: 6.2g P * (1 mol / 31g) * (P2O5 / P = (1/4)) * (141 g/mol) = 11.0 g Vậy nên đáp án là C. 11,0 g.