A solution is prepared by dissolving 0.6706 g oxalic acid \(\left(\mathrm{H}_{2} \mathrm{C}_{2} \mathrm{O}_{4}\right)\) in enough water to make 100.0 \(\mathrm{mL}\) of solution. A 10.00-mL aliquot (portion) of this solution is then diluted to a final volume of 250.0 mL. What is the final molarity of the oxalic acid solution?

The final molarity of the oxalic acid solution can be calculated using the following steps: 1. Calculate moles of oxalic acid in the initial 100 mL solution: \(Moles = \frac{0.6706\ g}{90.04\ g/mol} \approx 0.00745\ mol\). 2. Determine the concentration of oxalic acid in the initial 100 mL solution: \(Molarity = \frac{0.00745\ mol}{0.1\ L} = 0.0745\ M\). 3. Calculate moles of oxalic acid in the 10 mL aliquot: \(Moles\ in\ aliquot = 0.0745\ M \times 0.01\ L = 0.000745\ mol\). 4. Determine the final molarity of oxalic acid in the final 250 mL diluted solution: \(Final\ Molarity = \frac{0.000745\ mol}{0.25\ L} = 0.00298\ M\). Thus, the final molarity of the oxalic acid solution is approximately \(0.00298\ M\).