Pestle Analysis Lab

In the last two weeks, Roundup was added to water and the spectra were measured. The initial test ranging from 1% to 100% was to concentrated. This was indicated because the spectra’s absorbances were larger than one. Furthermore, when looking at figure 1, once above 0.30% data flattens off. Once the range was narrowed with serval more trial the range being now sampled is between 0.01 % to 0.30%. The lambda max is ranging from 307 to 309 wavelengths. Glyphosate’s structure contains three major functional groups which include carboxylic acid, phosphonate, and an amine. The carboxylic acid has a n to pi star transition state and a pi to pi star transition state. The typical transition state for a n to pi star is approximately 300 nm. The other functional groups can cause the lambda max to shift closer to the visible region. In addition, other compounds within Roundup may be causing a shift. …show more content…
If there was a difference between the two, it would imply that there are other matrices affect the Roundup. When looking at figure 2 and figure 4, the calibration curves are similar. This can be seen when looking at the dilution 0.2% where both graphs are above an absorbance of 1. Also, the relative deviations are small. With both the serial and stock dilution, the pH was the same. The purpose of determining the pH is for a future test. The pH was relatively the same as the distilled water. When testing the roundup at 100%, the pH varied from 4.12 to 4.77. The future experiment would be to pH adjust the water of each set of samples in order to see if there is a change in the spectra. This would be done with both acidic and basic