Answer:
2.95 * 10^23 of phosphorus atoms
Explanation:
molar mass of diphosphorus pentoxide = 283.886 g/mol
Number of moles in 140 g = 140 g/283.886 g/mol = 0.49 moles
1 mole of P2O5 contains 6.02 * 10^23 phosphorus atoms
0.49 moles of P2O5 contains 0.49 * 6.02 * 10^23/1 = 2.95 * 10^23 of phosphorus atoms
