Question

41) True or False? Dative bonding occurs when both atoms in a bond contribute an electron 11 point] EXTRA CREDIT: 1) The MacArthur-Forrest process is a metallurgical technique for extracting gold from low-grade ore by converting the gold to water soluble aurocyanide metallic complex ions. It is the most commonly used process for gold extraction. Subsequent processing of aurocyanide allows recovery of pure gold. 4 Au + 8 NaCN + O2 + 2 H20 4 NaAu(CN)2 + 4 NaOH Using 150,000.0 Liters of 0.0025 M NaCN (sodium cyanide: MW=49.0 g/mol), what theoretical weight in kilograms of gold metal [Atomic Weight = 197.0 g/mol) might be obtained following the reprocessing of the NaAu(CN)2 formed? 17 points Dataceium hudmvide (KOH) is a strong base. For a solution that is 0.450 M, determine the follow

Answer 1

4 Ma [AUCONI 4 ЧM4OH 4 AU+ 8 Nach +O2 + 2H₂O Molanity of Mach = 0.0025m Volume - 150,000 litre number of moles Molasity - Volumes in Litre Molanity & Volume in litre ( number of moles = 0.0025 * 150,000 = 375 moles moles of Nach from above Reaction. & 8 mole Nach gives = 4 mole na AUCH 1 mole Nach gives & mole 375 mete Mach gives = 4*375 mole Ma [A400Mb] = 187·5 mole Molar mass of Ma[44CCM)2] = 23+ 197+(26)* 2 = 272 g/mole number of moles - mass- molar mays - mass fingm) = noch moles* molar mass = 272g/mole * 187.5 mole - 51000 gm mass of gold metal = 51kg.