Question

The following preparatory questions should be answered before coming to lab. They are intended to introduce you to several ideas that are important to aspects of the experiment. You must turn in your work to your instructor before you will be i allowed to begin the experiment. 1. Balance the three copper reactions: 1) Cu(s) + HNO3(aq) ii) Cu(NO3)2 (aq) + 2NaOH(aq) - iii) Cu(OH)2 (3) Cu(NO3)2 (aq) +NO2(g) + H2O (1) Cu(OH)2 (8) + NaNO (aq) CuO (s) + H20 (1) + CD 2. In reaction (1), suppose you add 4.0 mL of 6 M nitric acid to a sphere of copper metal that weighs 0.65 grams. Which reactant is the limiting reagent? (Show your work) Imole as cu react with mole as 63.5 gm of cu . U x 63gm alt 4 mol of 6M IH No Means o limiting one u. Wt xlovo = 1.008. 4 x 63gm af HNO₃ - 63.5 gm of ca CHEM1814-YEAR 2019-2020 1.668 g mah No.2 x 63.5 0.25

Answer 1

4 iy Cris) + 4HNO3(aq) - WWD), () + NO +24,060) ily Cu(NO3)2 (aq) + 2NaOH(aq) - COM, (s) + 2 NaNO3 (19) i Culoh), is) - Class + HOU) 27 Volume of HNO₃ = 4.0mL = 4.0x10 L Concentration of HNO₂ = 6.om = 6.0 mol/L no. of mole of HNO = 4.08103 LX 6.0 mal, = 24.0*10-? mol weight of les metal = 0.65g. no. of male of a = weight = 0.65g - 10.24x10 mol. molermans 63.5ginal In balanced chemical son (i) Imole u react with y mole MNO, then 10.24x10² mol ce react with 4 x 10.24 x 103 = 40.96X163 mol HNO, but we have only 24.0 x103 mos HNO Hence, HNO3 is the limiting reagent. Hence, HNO is the limiting reagent.