6. During a titration, 10.00 mL of an acidie solution of unknown concentration was placed in a 125 mL Erlenmeyer flask. To this was added 20.0 mL of deionized water and two drops of phenolphthalein indicator, making the total volume in the flask 30.0 mL . A subsequent titration revealed that the concentration of the original unknown acid was 0.868 M . What was the concentration of the diluted acid in the Erlenmeyer flask? Calculation: \( (0.868)(0.01 \mathrm{~L})=0.03 \mathrm{~L} \)

To find the concentration of the diluted acid in the Erlenmeyer flask, let’s first acknowledge that dilution changes concentration but not the number of moles. The number of moles of the acid originally can be calculated using the concentration and volume before dilution. In this case, \(0.868 \, \text{M} \times 0.0100 \, \text{L} = 0.00868 \, \text{moles}\). After dilution, the total volume is 30.0 mL or 0.0300 L. To find the new concentration, we divide the number of moles by the new volume: \(C = \frac{0.00868 \, \text{moles}}{0.0300 \, \text{L}} \approx 0.289 \, \text{M}\). Interestingly, the concept of dilution plays a crucial role in many real-world processes, from preparing solutions in a laboratory to creating the perfect lemonade at a summer picnic! Understanding how concentrations change when solutions are mixed is essential in everything from pharmaceuticals to culinary arts, ensuring that we achieve the desired effects or flavors. When handling titrations, one common mistake is forgetting to account for the total volume after dilution when calculating the new concentration. Always double-check your volume conversions and calculations! Another tip is to ensure thorough mixing after dilution to verify that the solution is homogenous before conducting any subsequent experiments or titrations. Happy titrating!