A sample of metal was dissolved and mixed into a

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A sample of metal was dissolved and mixed into a solution to be analyzed in a spectrophotometer. This spectrophotometer has a PDA, which allows for a spectrum of wavelengths simultaneously. This let us find the concentration of Mn and Cr without running it more than once per trial. Sulfuric acid is used as a blank because it is very similar to the solution so that it can account for as many impurities as possible. At the end, it was found that the percent weight is 0.33% for Mn and 21.6%for Cr with a %RSD of 38.3% and 3.90% respectively. Also, the standard deviation was 0.127 for Mn and 0.843 for Cr. The confidence interval is 0.120 for Mn and 0.800for Cr.Conclusion
An unknown sample of metal was dissolved and mixed into a solution to be analyzedin a spectrophotometer. This spectrophotometer has a PDA, which allows for a spectrum of wavelengths simultaneously. This is handy when finding the concentration of multiple samples. Sulfuric acid is used as a blank because it is very similar to the solution so that it can account for as many impurities as possible. At the end, it was found that the percent weight is 0.33% for Mn and 21.6% for Cr with a %RSD of 38.3% and 3.90% respectively. Also, the standard deviation was 0.127 forMn and 0.843 for Cr. The confidence interval is 0.120 for Mn and 0.800 for Cr. As seen from the values, there is a small amount of deviation. This comes from random and human error. Human error comes from minor mistakes like not exactly hitting the meniscus by one drop. Error can come from transferring samples from containerto container. Another error comes from the evaporation that would escape during the experiment. Also, with flask 1, when adding in the long list of chemicals, the water was forgotten at the beginning of the heating process and was immediately added when remembered. However, this proved to have affected the coloring in comparison to the other two flasks. To decrease error, more trials could be done to outweigh any outliers and increase precision.

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