When describing the production of an Unknown Cobalt (III) complex [Co(NH3)nL(6-n)]Yq we have come up in  the Part D, that Cl- must be present in the cobalt compound, while H2O and NO2 are not likely to be the ligands. It is clear due to the color of the compound, which is the darkest among all the unknown cobalt compounds. The resulted compound from the Cobalt (III) ion to H2O or NO2 bounding would be lighter in color (Werner Characterization table, part D). In addition, HNO3 is never involved in the production of the Cobalt compound, therefore NO2 is not likely to be an option in this reaction.

According the research, possible molecular formuli can be [Co(NH3)5Cl]Cl2, [Co(NH3)4Cl2]Cl or Co(NH3)3Cl3, and their molar masses are 250.5 g/mol, 233.5 g/mol and 216.5 g/mol respectively. The calculations of the molar mass is 269, which implies in Part A that the possible molecular formula is [Co(NH3)5Cl]Cl2. The results of this hypothesis are supported by the experiments held in part C. Among the three possible formuli, only [Co(NH3)5Cl]Cl2 breaks into three ions when dissolved in water. Nonetheless, the part B indicates slight deviations of the results. It appears that the error in the part B mainly comes from the inability of capturing the bubbles formed by the reaction. Consequently, the number of NH3 ligand per Cobalt compound molecule might be underestimated. When viewing the success rate of the results indicated in all four part we can mark that the least accurate results were designated in Part A and B, following by a relatively good description in Part C, and closing by Part D, which gives the best results. Therefore, the most accurate calculations of the molecular formula are based on the results of the experiments found in part C and D. Nonetheless, the results from Part A and B can be used as a reference.

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