The concentrations and absorbances of the three samples of working analyte are

# The concentrations and absorbances of the three

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solution. The concentrations and absorbances of the three samples of working analyte are determined to be equal and consistent to 381ppm and 0.386 respectively. There would be no relative standard deviation and the confidence interval is just the concentration itself. The initial analyte’s concentration is determined to be consistent to 2574ppm, after multiplying working sample ppm to the dilution factor that is 50mL/7.4mL from the 7.4 aliquot being diluted to 50mL. There is also no RSD and the CI is just the concentration of itself. The error percentage from the theoretical value of 2500ppm is 2.96%, this error is cleary seen on the y-intercept value of the calibration curve. The y-intercept determines if there is any deviation on the linear relationship. In an ideal equation the y-intercept should be equal to zero, but the Beer’s Law has its own set of limitations and the working environment is not a vacuum that is strictly controlled. To completely understand the deviation, the limitations of Beer’s law and the errors in the experiment were presented and discussed in the next paragraphs. In this experiment, the analysis has some errors, clearly signified by the y- intercept and the percent error. The miscalculations could have resulted from the inconsistency of the purity of solution, dust may have settled in, which increases the absorbance of the analyte. Dirt and fingerprints could also be be present, this limits the transmittance. Stray light and iproper cleaning of cuvette also affects the absorbance. The other factors are the Beer’s Law limitations. The Beer’s Law limitations are grouped into three categories, namely: real deviations, chemical deviations and instrumental deviations. Real deviations are the fundamental limits of the Beer’s Law, since it the law only applies to dilute solutions. Solutions whose molarity is exceeding 0.01M are inapplicable with the Beer’s Law because the average distances of the molecules or ions are diminished to the extent that they affect each other’s charge distribution and absorption. This limit also applies to dilute solutions whose absorbers are in contact with a high concentration of other species of other species. Chemical deviations on the other hand are the errors that we are unaware of. These are the problems regarding the equilibrium of the solution. They are usually uncorrectable (Christian, 503- 505). The last limitation is the instrumental deviation, which is just the problems with the spectrophotometer itself or the containing cell. Problems arise when the use of a monochromatic light is not observed, as differences in wavelength arise, the linearity deviates. The position of the cuvette also affects the retrieved data, the path length of light should be constant at all times. The last possible factor is the stray light, a radiation that is outside the nominal wavelength band chosen for determination. It usually comes from reflection of surfaces (Christian, 504-505) Better results could have been obtained if the experiment itself is

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