a. You want to prepare 1.00 L of a buffer solution with a pH of 3.5. You are given an 0.45 M solution of nitrous acid, HNO2, and an 0.68 M solution of NaOH.  What volume of each of these solutions must be mixed in order to get the desired buffer solution?  Use the simultaneous equations method to solve this problem.     b)If the acid used in a. was nitric acid, HNO3, could the same buffer solution be made? Briefly explain.     c) If the buffer solution prepared in a. also contained ~10–6M Ni2+ and ~10–6 M Pb2+ , could those metal ions be separated from each other by saturating the solution with H2S? Explain your answer by showing the necessary calculations.

a.  An aqueous solution contains 0.20 M hydrocyanic acid.One Liter of this solution could be converted into a buffer by the addition of:(Assume that the volume remains constant as each substance is added.) 0.21 mol KCN 0.21 mol HI 0.20 mol KBr 0.050 mol Ba(OH)2 0.10 mol HI   b. An aqueous solution contains 0.18 M ammonium iodide. One liter of this solution could be converted into a buffer by the addition of:(Assume that the volume remains constant as each substance is added.) 0.18 mol HNO3 0.17 mol KI 0.08 mol HNO3 0.08 mol KOH 0.17 mol NH3 c.  An aqueous solution contains 0.33 M sodium fluoride.One liter of this solution could be converted into a buffer by the addition of:(Assume that the volume remains constant as each substance is added.) 0.16 mol KOH 0.33 mol HCl 0.32 mol NaCl 0.32 mol HF 0.16 mol HCl

Titrations (weak acid/strong base)

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