Question

(20 points) A metal plating facilitate produces hazardous waste that contains 50 mg/L of copper (Cu). Caustic soda (i.e. sodium hydroxide; Na OH) is added to the waste to raise

the pH and cause precipitation of copper hydroxide (Cu(OH)2) according to the followingreaction: Copper hydroxide has a Ksp of 2.00×1019. The goal of the treatment process is to reduce the copper concentration to 1.3 mg/L. Determine the hydroxide concentration (in moles/L) to which the solution needs to be raised to achieve the target copper concentration. What is the pH of this solution?

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