How many grams of 15% potassium hydroxide solution are needed to fully react with 14.2 g of phosphorus pentoxide?
- 200 g
- 224 g
- 112 g
- 448 g
📝 Detailed explanation
P₂O₅ + 6KOH → 2K₃PO₄ + 3H₂O.Moles P₂O₅ = 14.2 / 142 = 0.1 mol.
Moles KOH needed = 0.1 × 6 = 0.6 mol.
Mass KOH = 0.6 × 56 = 33.6 g.
Mass solution = 33.6 / 0.15 = 224 g.