Chapter 33

The \(\mathrm{Cu}^{2+}\) ions in this experiment are produced by the reaction of \(1.0 \mathrm{g}\) of copper turnings with excess nitric acid. How many moles of \(\mathrm{Cu}^{2+}\) are produced?

Why isn't hydrochloric acid used in a direct reaction with copper to prepare the \(\mathrm{CuCl}_{2}\) solution?

How many grams of metallic copper are required to react with the number of moles of \(\mathrm{Cu}^{2+}\) calculated in Problem 1 to form the CuCl? The overall reaction can be taken to be: $$ \mathrm{Cu}^{2+}(\mathrm{aq})+2 \mathrm{Cl}^{-}(\mathrm{aq})+\mathrm{Cu}(\mathrm{s}) \rightarrow 2 \mathrm{CuCl}(\mathrm{s}) $$

A sample of the compound prepared in this experiment, weighing 0.1021 g, is dissolved in HNO, and diluted to a volume of \(100 \mathrm{mL}\). A \(10-\mathrm{mL}\) aliquot of that solution is mixed with \(10\ \mathrm{mL} 6\ \mathrm{M}\ \mathrm{NH}_{3}\). The \(\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}^{2+}\right]\) in the resulting solution is found to be \(5.16 \times 10^{-3} \mathrm{M}\)a. How many moles of Cu were in the original sample, which had been effectively diluted to a volume of \(200 \mathrm{mL} ?\) moles______. b. How many grams of Cu were in the sample? g_______ c. How many grams of Cl were in the sample? How many moles? g______moles______. d. What is the formula of the copper chloride compound?