This document presents an analysis of the reaction between FeCl3 and KSCN, including the determination of the equilibrium constant. The results show a significant difference between the experimental and theoretical values, highlighting the importance of considering factors such as temperature and measurement uncertainty. The document provides a detailed example of calculation and discusses the implications of the findings.
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[...] Uncertainty: Finally, the equilibrium constant of the reaction is given by: L/mol. Uncertainty DISCUSSION The average value of the equilibrium constant is very different (by a factor of from the theoretical value. Among the factors that can explain this difference we note: - The ambient temperature different from the given temperature for the theoretical value - The measurement of absorbance performed in part during the reaction, as the Fe3+ It is introduced in excess, it will remain in the solution. [...]
[...] TABLEAU II Ballon number Concentration of FeCl3 (mmol/L) Volume of FeCl3 to take 1 2 3 4 5 Example of calculation (bottle of the volume of mother solution to take: Dilution factor: Volume to be taken: . TABLEAU III Aqueous solutions of FeSCN2+ 1 2 3 4 5 mmol/L mmol/L Absorbance mmol/L mmol/L mmol/L medium Ambient Temperature Examples of calculations (column in solution in solution I mix 4.0 mL of FeCl3 and 4.0 mL of KSCN so we have a total volume of 8.0 mL and a dilution factor . So we have for solution is determined with respect to the absorbance using the calibration curve. According to the curve we have with so . [...]
