CHEM 105 1nd Edition Lecture 8Outline of Last Lecture • Ionic compounds are strong electrolytes.• Molecular compounds that are not acids are non-electrolytes.• Acids are molecular compounds that transfer hydrogen ions to water to make hydroniumions (see page 148).• Strong acids completely transfer the available hydrogen ions. They are strong electrolytes.• There are six strong acids. You will need to know these six. There is a table of them somewhere in chapter 4. Find it!• Weak acids only partially transfer the available hydrogen ions. They are weak electrolytes.• A base accepts H from another substance. Hydroxide salts are strong bases (strong electrolytes). +• Other bases (ammonia and carbonate, for example) are weak bases. They accept less H than + there are base molecules. They are weak electrolytes.Outline of Current Lecture • Solubility rules• precipitation reactions Current LectureSolubility rules is hierarchical list of rules (the first applicable rule supercedes latter rules).1. All sodium, potassium, lithium and ammonium salts are soluble.2. All nitrates, acetates and perchlorates are soluble [Ag(CH3CO2) is slightly soluble]3. All silver, lead and mercury salts are insoluble. [Mercury(II)chloride is soluble. Mercury(II)bromide is slightly soluble.]4. All chlorides, bromides and iodides are soluble.5. All carbonates, phosphates, sulfides, and oxides are insoluble.6. All hydroxides are insoluble. [Barium hydroxide and strontium hydroxide are soluble,calcium hydroxide is slightly soluble].7. All sulfates are soluble. [Except those of barium, strontium and calcium].Q: Write equations for what happens when solutions of the following are mixed:calcium chloride and lead(II) nitrate• CaCl2(aq) +Pb(NO3)(aq) ----> Ca(NO3)2(aq) +PbCl2(s)sodium phosphate and nickel(II) nitrate• Na3PO4(aq) +3Ni(NO3)(aq) -----> 6NaNO3(aq) + Ni3(PO)2(s)copper(II) sulfate and potassium perchlorate• CuSO4(aq) + 2NaClO4(aq) -----> Cu(ClO4)2(aq) +Na2SO4(s)cobalt(II) sulfate and potassium hydroxide.• COSO4(aq) +2KOH(aq) -----> CO(OH)2(s) + K2SO4(aq) Q: Write overall ionic equations and net ionic equations for the four “reactions” above.• Overall : Ca2+(aq) +2Cl-(aq) +Pb3+(aq) +2NO3-(aq) ----> Ca2+(aq) +2NO3-(aq) +PbCl2(s) Net : Pb2+(aq) + 2Cl-(aq) -----> PbCl2(s)• Overall: 6Na+(aq) +2PO4-(aq) +3Ni2+(aq) +6NO3-(aq) -----> 6Na2(aq) +6NO3-(aq) +Ni3(PO4)2(s)Net: 3Ni2+(aq) +2PO4-(aq) -----> Ni3(PO4)2(s)• Overall: Ca2+(aq) +SO4-(aq) +2Na+(aq) +2CIO4-(aq) -----. Ca2+(aq) +2CIO4(aq) +2Na+(aq) +SO2-(aq)Net: No Reaction• Overall: CO2+(aq) +SO4-(aq) +2K+(aq) +2OH-(aq) -----> CO(OH)2(s) +2K+(aq) +SO4-(aq)Net: CO2+(aq) + 2OH-(aq) ---->
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