please help me. (A) Balance the copper reactions: (i ) Cu(s) + HNO3(aq) -> Cu(NO3)2 (aq) + NO2(g) + H2O (l) (B) In reaction (i), suppose that you add 12.8 mL of 6 Mnitric acid to a spheref copper metal that weighs 1.06 grams. Whicheactant is thelimithing reagent? please help me. (A) Balance the copper reactions: (i ) Cu(s) + HNO3(aq) -> Cu(NO3)2 (aq) + NO2(g) + H2O (l) (B) In reaction (i), suppose that you add 12.8 mL of 6 Mnitric acid to a spheref copper metal that weighs 1.06 grams. Whicheactant is thelimithing reagent?
Explanation / Answer
Cu(s) + 4 HNO3(aq) -> Cu(NO3)2 (aq) + 2NO2(g) + 2 H2O (l) Moles of nitric acid = Molarity * volume =6 m * 0.0128 L =0.0768 moles Moles of copper = Mass / atomic mass =1.06 g / 63.54 g/mol =0.0166 In the equation, 1 mole of copper can react with 4 moles ofnitric acid. So 0.0166 moles can react with 0.0664 moles ofnitric acid. As nitric acid is in excess, it means copper is the limitingreagent.