Preparation of CuCl

Reactions: 1) Cu(S) + 4HNO3(aq) -> Cu(NO3)2(aq) + 2NO2(g) +2H2O(l) 2) 2HNO3(aq) + Na2CO3(s) -> H2O(l) + CO2(g) + 2NaNO3(aq)3)Cu(NO3)2(aq) + Na2CO3(s) -> CuCO3(s) + 2NANO3(aq) 4)CuCO3(s) +2HCL(aq) -> CuCl2(aq) + H2O(l) + CO2(g) 5)CuCl2(aq) + Cu(s)-> 2CuCl(s)

Weight of copper: 1.023g

Volume of Added Nitric Acid: 5.5 mL

Total weight of added Sodium Carbonate: 3.85g

Weight of Watch Glass and filter paper: 51.533g

Weight of Watch Glass, Filter Paper and CuCl Precipitate:53.524

Experimantal Yield of CuCl: 1.991g

Theoretical Yield of CuCl: 3.187g CuCl

Percent Yield of CuCl: 62.47%

1) Based on the amounts of copper metal and nitric acid you usedin the 1st reaction, calculate the number of moles ofHNO₃ there are in excess. Concentrated nitric acid has aconcentration of 15.8 M.

2. Using the moles of HNO₃ you calculated and themoles of Cu(NO₃)₂ produced from the 1streaction, calculate the total mass of sodium carbonate needed forthe second and third reactions. Did you add enough sodium carbonatein the experiment?

3. What observation suggests that copper was added in excessduring the last reaction?

4) Why might a student obtain a percent yield less than 100% forthis preparation?

5) Copper metal reacts with dilute nitric acid by the followingreaction.

3Cu(s)+ 8HNO₃(aq)->3Cu(NO₃)₂(aq) + 2NO(g) +4H₂O(l)

If this reaction took place rather than the 1st reaction, wouldyour yield of CuCl be affected assuming you started with the sameamount of copper metal? Explain your answer.

6) Could we use HCl to dissolve the copper metal instead ofnitric acid in the first reaction? Explain your answer.

7) Given the following three sequential reactions:

a) N₂(g) + 3H₂(g) ->2NH₃(g)

b) 4NH₃(g) + 5O₂(g) -> 4NO(g) +6H₂O(g)

3) 2NO(g) + O₂(g) -> 2NO₂(g)

What mass of hydrogen gas is needed to produce 165.0 kg ofnitrogen dioxide?