Reactions of Copper Experiment. Copper metal reacts with aqueous nitric acid to

Question

Reactions of Copper Experiment. Copper metal reacts with aqueous nitric acid to produce copper (II) nitrate, nitrogen dioxide and water. a. Write a balanced chemical equation describing this reaction. Include the phase designation for each reactant and product (solid, liquid, gas, aqueous). b. Assuming that you start with 0.1059 g of copper metal (63.546 g/mol), what volume, in mL of 9.0 M nitric acid would be required for all the copper to react? c. What two observations would be important for this reaction to verify that enough nitric acid was added and the reaction has gone to completion?

Explanation / Answer

a)

balanced equations

copper metal = Cu(s)

Aqueous nitric acid = HNO3(aq)

copper (II) nitrate = Cu(NO3)2(aq)

nitogren dioxide = NO2(g)

water = H2O(l)

so:

Cu(s) + HNO3(aq) --> Cu(NO3)2(aq) + NO2(g) + H2O(l)

balance:

Cu(s) + 4HNO3(aq) --> Cu(NO3)2(aq) +2NO2(g) + 2H2O(l)

b)

mol of copper = mass/MW = 0.1059/63.546 = 0.0016665

mol of nitric acid = Molarity * Volume = M*V = (V)(9M)

now...

we know that, ratio is 1 mol of copper = 4 mol of HNO3

so

0.0016665 mol of Cu = 4*0.0016665 =0.006666 mol of HNO3

now

M = mol/V

V = mol/M = (0.006666) / 9 = 0.00074066 Liters = 0.00074066*10^3 mL = 0.74 mL

c)

observations:

NO2(g) production of gas

pH change to about pH = 7

Related Questions

Navigate

• Browse (All)
• Browse R
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.