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How would you calculate the mass of zinc in a 1.000 g sample of a brass alloy using gravimetric analysis?

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To calculate the mass of zinc in a 1.000 g sample of a brass alloy using gravimetric analysis, follow these steps:1. Dissolve the brass sample: First, dissolve the 1.000 g brass sample in a solution of nitric acid  HNO3 . This will convert the zinc and copper in the brass into their respective nitrates  Zn NO3 2 and Cu NO3 2 .2. Precipitate the zinc: Add an excess of sodium hydroxide  NaOH  solution to the dissolved brass sample. This will cause the zinc to precipitate as zinc hydroxide  Zn OH 2 , while the copper will remain in solution as copper nitrate.Zn NO3 2 + 2NaOH  Zn OH 2 s  + 2NaNO33. Filter and wash the precipitate: Filter the mixture to separate the zinc hydroxide precipitate from the copper nitrate solution. Wash the precipitate with distilled water to remove any remaining soluble impurities.4. Convert zinc hydroxide to zinc oxide: Gently heat the zinc hydroxide precipitate to convert it into zinc oxide  ZnO  and water. This step is necessary because zinc oxide is easier to weigh accurately than zinc hydroxide.Zn OH 2 s   ZnO s  + H2O g 5. Weigh the zinc oxide: After cooling the zinc oxide to room temperature, weigh it using an analytical balance.6. Calculate the mass of zinc: Use the stoichiometry of the reaction between zinc hydroxide and zinc oxide to determine the mass of zinc in the original brass sample. The molar ratio of Zn to ZnO is 1:1.First, calculate the moles of ZnO:moles of ZnO = mass of ZnO / molar mass of ZnONext, calculate the mass of Zn:mass of Zn = moles of ZnO  molar mass of Zn7. Report the mass of zinc in the 1.000 g brass sample.By following these steps, you can accurately determine the mass of zinc in a brass alloy using gravimetric analysis.

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