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Choose a reagent that will separate the cations in the following pair: AgNO3(aq) and Co(NO3)2(aq). Hot water NH3HClNaCl Question 9 Which of the following reactions does not form a precipitate? AgCl(s)+2NH3(aq)PbC12(aq)+K2CrO4(aq)Pb(NO3)2(aq)+2HCllaqHg2Cl2(s)+2NH3(aq) A solution may contain one or more of the Group I cations. A white precipitate forms when 6MHCl is added to the solution. The precipitate is insoluble in hot water. The precipitate is then found to be completely soluble in 6MNH3. Indicate whether Pb2+ is present, undetermined, or absent. present undetermined absent Question 3 A solution may contain one or more of the Group I cations. A white precipitate forms when 6MHCl is added to the solution. The precipitate is insoluble in hot water. The precipitate is then found to be completely soluble in 6MNH3. Indicate whether Hg22 is present, undetermined, or absent. present undetermined abseot A solution may contain one or more of the Group I cations. A white precipitate forms when 6MHCl is added to the solution. The precipitate is insoluble in hot water. The precipitate is then found to be completely soluble in 6MNH3. And reprecipitates after adding HNO3. Indicate whether Ag+is present, undetermined, or absent. present undetermined absent Question 5 Indicate the color that each of the following would exhibit. 2. PbCrO4(5) 2K2CrO4 (aq) 1. White 1. A5Cl(s) 2. Yellow 3. HgNH2G/s) plus Hg 3. Gray Choose a reagent that will separate the cations in the following pair: AgCl(s) and PbCl2(s). Hot water NH3 HCl NaOH Question 7 Choose a reagent that will separate the cations in the following pair: AgCl(s) and Hg2Cl2(s). Hot water NH3 HCl NaOH To confirm presence of Ag+ ions, nitric acid is added to the silver/ammine complex. Why? Nitric acid destroys the silver/ammine complex Silver chloride precipitates as silver nitrate Nitric acid neutralizes Silver Hydroxide Nitric acid oxidizes the silver/ammine