Please answer part c of this question only.
A vanadium coordination complex has a formula V(NH3)xCly. Use the following analytical data to determine the chemical formula of this complex and write chemical equations that illustrate the course of this analysis.
A 125 mg sample of the above compound was reacted with excess nitric acid:
25.0 mL of 0.232 M HNO3
Calculate the number of mmols of nitric acid added.
Write the chemical reaction of nitric acid with ammonia.
The excess nitric acid was determined by titration and the methyl red (pKa = 4.95) endpoint required 13.8 mL of 0.178 M NaOH. Determine the mmols of excess nitric acid.
Comment on why methyl red was used as the indicator rather than phenolphthalein (pKa = 9.4).
Use your results from a and c to determine the number of mmols and mass (mg) of ammonia in the original sample.
The solution from the titration is acidified and then treated with 205 mg AgNO3 and the white precipitate that forms weighs 158 mg. Write a chemical reaction for this precipitation reaction and determine the number of mmol and mass (mg) of chloride in the sample.
Use the data above to determine the mass and number of mmols of vanadium in the original sample and determine the empirical formula of V(NH3)xCl.