StoichiometryHardQuestion 600067
Question
X g of hydrated oxalic acid (H₂C₂O₄·2H₂O, M=126) dissolves to give 100 mL of solution. 10 mL of this neutralises 15 mL of 0.1 M NaOH. X is:
- A0.473 g
- B0.945 gCorrect
- C0.315 g
- D0.630 g
Correct answer
0.945 g
Explanation
Moles NaOH = 0.015×0.1 = 0.0015 mol. H₂C₂O₄ has 2 acidic protons → moles H₂C₂O₄ in 10 mL = 0.0015/2 = 0.00075 mol. In 100 mL: 0.0075 mol. X = 0.0075×126 = 0.945 g.