Methyl Orange Synthesis Lab Report

Before proceeding with the experiment, the theoretical yield was calculated to be 0.945 g. After preparation of the product, the theoretical yield was used to determine the percent yield, which was found to be 79%. Due to this reasonable yield, it was concluded that the synthesis of methyl orange had been successful. Data Table 1 gives the results and observations that were recorded throughout the preparation of methyl orange. According to literature, methyl orange is an azo dye that forms orange crystals. However, the product that formed was orange with gold crystals. This appearance does not have any negative implications though. The experiment was carried out smoothly with no errors. Nevertheless, some mass could have been loss during the heating or during the transfer of the crystals into a vacuum filtration apparatus. When the dried crystals were collected from the Buchner funnel, some product was also lost. The loss of crystals was not significant though, as a decent percentage was found for the percent yield. This means that a sufficient amount of methyl orange was synthesized.

Indicator tests were performed to prove that the synthesized methyl orange crystals can act as successful acid-base indicators. Data Table 1 also shows the observations from these tests. Samples of methyl orange crystals were placed into three test tubes, each containing water, HCl and NaOH, respectively. The crystals in the test tube of distilled water acted as the control group; the color of the solution turned yellow, which confirmed that the pH of water is neutral. A sample of the methyl orange crystals in HCl yielded a red solution, while another sample of the crystals in NaOH showed a light orange to yellow solution. These tests prove that the methyl orange can respond to pH by changing