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Determination of the equilibrium constant concentration

por Alex Dixon (2019-08-23)


Fe3 + + CSN- <-> Fe (SCN) 2+ reaction is simple and easy to observe, Fe3 + is pale yellow, CSN- is colorless, while Fe (SCN) 2+ is deep red (maximum absorption a447 nm). Determination of the equilibrium constant concentration of this reaction appears in many laboratory practices. In this manuscript, the concentration of Fe (SCN) 2+ is determined using a calibration curve and equilibrium constants are determined in 8 mixtures of Fe3 + (0.002 mol L-1) and SCN- (0.002 mol L-1). The concentration of Fe (SCN) 2+ complex is determined using absorbance measured at 447 nm. Determination of complex concentration is also performed using digital images, where solutions are placed in 96-well plates and a digital image is obtained using a flatbed scanner. RGB (red, green and blue) values are extracted from each well simultaneously by ImageJ's ReadPlate plugin. The two-sample t-test for the mean shows that equilibrium constants determined with absorbances, measured at 447 nm, and B values extracted from digital images, are equivalent within a 95% confidence interval. Academics have the opportunity to verify the relevance of the linear model of the proposed analytical curve using the correlation coefficient, analysis of variance (ANOVA) and residuals graphs. A Microsoft Excel spreadsheet is available in Google Drive to organize exported ImageJ data, generate the analytical curve and equilibrium constant across the eight mixtures of Fe3 + and SCN-. Get more details from an affordable essay writing service and study more about the topic.