Copper is an excellent electrical conductor widely used in making electric circuits. In producing a printed circuit board for the electronics industry, a layer of copper is laminated on a plastic board. A circuit pattern is then printed on the board using a chemically resistant polymer. The board is then exposed to a chemical bath that reacts with the exposed copper, leaving the desired copper circuit, which has been protected by the overlaying polymer. Finally, a solvent removes the polymer. One reaction used to remove the exposed copper from the circuit board is

A plant needs to produce 5000 circuit boards, each with a surface area measuring 2.0 in. × 3.0 in. The boards are covered with a 0.65-mm layer of copper. In subsequent processing, 85% of the copper is removed. Copper has a density of 8.96 g/cm3. Calculate the masses of Cu(NH3)4Cl2 and NH3 needed to produce the circuit boards, assuming that the reaction used gives a 97% yield.

Transcribed Image Text:

Cu(s) Cu(NH3)4Cl2(a 4 NH3(aą)> 2 Cu(NH3)4Cl(aą)