Question

Dissolution of Copper Metal Copper reacts readily with strong oxidizing agents (substances that readily remove electrons from other suhstances-i.e... Cu- Cu2 +2e). In this experiment, aqueous nitric acid, HNO, oxidizes copper metal to the copper(II) ion (opening photo): Cu(s) +4 HNO,(aq)Cu(NO)(aq) +2 NO (8) +2 H,0( .Cu HNO3 Cu(NO3)2 (28.1) CuSO The products of this reaction are copper(II) nitrate, Cu(NO)2 (a water-soluble salt that produces a blue solution), and nitrogen dioxide, NO2 (a dense, toxic, red-brown gas). The solution remains acidic because an excess of nitric acid is used for the reaction, -Cu(OH)2 CuO 4. Experimental Procedure, Part A.2. What volume, in drops, of 16 M (conc) HNO, is required to react with 0.0214 g of Cu metal? See equation 28.1. Assume 20 drops per milliliter. 100 ceer to untelmort

Answer 1

1. First, the mass of copper was converted to moles.

2. 4 moles of HNO3 is required for 1 mole of copper. So, 4 is multiplied to determine the number of moles HNO3 needs.

Cu (s) + 4HNO₃ (aq) - Cu(NO3)2 (aq) + 2ND 2(g) + 2H₂0 (1) Given : Mars of Cu = 0.0214g Assume 20 drops for Int. Concentration of HNO₃ = 16M Note: & moles of HNO₃ are required for each mole of Cu Mut. of Cu = 63.5469 1 mol of Cu x A not of HNO₃ 63.546g Cu Imol en Moles of HNO₃ required = 0·02149 cu x = 0.001347 moles Now, 4 mol HNO3 1000ml lime 20 drops = 0.0002 mole/ drop . No. of drops of HNO₃ (Molume) required (x drops) & (0.0002 mole/drop) = 0.001347 moles n = 0.0013 47 drops at. 0.0002 In = 6.735 ~ 7 dreops