Complete Ionic Equation Net Ionic Equations

Electrolytes from Conductivity Test Electrolytes are substances whose aqueous solution is a conductor of electricity All electrolyte have ions dissolved in water Conductor of electricity? Pure water: No! No ions are present Table salt (NaCl) solution: Yes! Na+ & Cl- 2

Dissociation Dissociation: When ionic compounds dissolve in water, the anions and cations are separated from each other - however not all ionic compounds are soluble in water! When compounds containing polyatomic ions dissociate, the polyatomic group stays together as one ion

Electrolytes Strong electrolytes: all the electrolyte molecules or formula units are separated into ions. Table salt (NaCl) Non-electrolytes: none of the molecules are separated into ions. Table sugar (C12H22O11), all gases (CO2), water. Weak electrolytes: a small percentage of the molecules are separated into ions. Acetic acid (Vinegar, CH3COOH), ammonia in water (NH3). 4

Strong Electrolytes Salts = water soluble ionic compounds NaCl, NH4C2H3O2, Ba(NO3)2, FeBr3, CuSO4 Strong Acids = completely dissociate to form H+ ions in water solution. HCl, HBr, HI, HNO3, H2SO4, HClO4 Strong Bases = water soluble metal hydroxides (OH-) Metal hydroxide of ALL GIA metals such as NaOH, KOH, etc. Lower GIIA hydroxides: Ca(OH)2), Sr(OH)2, Ba(OH)2 5

Dissociation Potassium iodide dissociates in water into potassium cations and iodide anions KI(aq)  K+(aq) + I-(aq) Copper(II) sulfate dissociates in water into copper(II) cations and sulfate anions CuSO4(aq)  Cu2+(aq) + SO42-(aq) K+ I- K I SO4 SO42- Cu Cu2+

Dissociation involving Polyatomic Ions Ammonium phosphate dissociates in water into ammonium cations and phosphate anions (NH4)3PO4(aq)  3 NH4+(aq) + PO43-(aq) PO4 PO43- NH4 NH4 NH4+ NH4 NH4+ NH4+

Ionic Equations Molecular equations uses Chemical formulas 2 KOH(aq) + Mg(NO3)2(aq) ® 2 KNO3(aq) + Mg(OH)2(s) Ionic equations describe the material’s structure when dissolved. ONLY aqueous strong electrolytes are written as ions soluble salts, strong acids, strong bases ALL OTHER compounds, Gases, Solids (such as insoluble substances), Liquids are written in molecular form 2K+(aq) + 2OH−(aq) + Mg2+(aq) + 2NO3−(aq) ® 2K+(aq) + 2NO3−(aq) + Mg(OH)2(s) 8 8

Net Ionic Equations Ions that are both reactants and products are called spectator ions 2K+(aq) + 2OH−(aq) + Mg2+(aq) + 2NO3−(aq) ® 2K+(aq) + 2NO3−(aq) + Mg(OH)2(s) Net ionic equation: An ionic equation in which the spectator ions are removed 2 OH−(aq) + Mg2+(aq) ® Mg(OH)2(s) 9 9

Example: Acid-Base neutralization NOTE: ONLY soluble salts, strong acids, and strong bases forms ions 2HNO3(aq) + Ca(OH)2(s) ® 2H2O(l) + Ca(NO3)2(aq) Types? ________ _____ _____ ________ Ionic equation: Spectator ions? net ionic equation: 10

Example: Gas-forming ionic equation ONLY soluble salts, strong acids, and strong bases forms ions Na2CO3(aq) + 2HCl(aq) ® 2NaCl(aq) + CO2(g) + H2O(l) Types? ________ ________ ________ ____ ____ Ionic equation: Spectator ions? net ionic equation: 11

Precipitation Reaction as ionic equation ONLY __________, ___________, and ___________ forms ions!!! K2CO3(aq) + 2 AgNO3(aq) ® 2 KNO3(aq) + Ag2CO3(s) Types? ________ ________ _______ ___________ Ionic equation: Spectator ions? net ionic equation: 12

More Practice – Write the ionic and net ionic equation K2SO3(aq) + 2HBr(aq) ® H2O(l) + SO2(g) + 2 KBr(aq) CO2(g) + 2KOH(aq) ® K2CO3(aq) + H2O(l) Ba(OH)2(aq) + H2SO4(aq) ® 2H2O(l) + BaSO4(s) 2LiOH(aq) + CuSO4(aq) ® Cu(OH)2(s) + Li2SO4(aq) 13

More Practice – Convert and Complete, then Write the ionic and net ionic equation chloric acid + ammonium sulfite  silver acetate + iron(III) bromide  zinc hydroxide + sulfuric acid  lithium sulfite + manganese(II) chloride  14

Weak Electrolytes Does NOT dissociate Weak acids (acetic acid, nitrous acid, hydrofluoric acid, etc), Weak base (ammonium hydroxide, etc), Insoluble salts largely remain undissociated in water HC2H3O2(aq)  H+(aq) + C2H3O2-(aq) NH4OH(aq)  NH4+(aq) + OH-(aq) PbCl2(s) CaCO3(s) BaSO4(s) Pure gas, liquid, or solid exists as non-dissolved states CO2(g), H2S(g), H2O(l), Al(s), Hg(s) 15

Write the ionic and net ionic equation involving weak or non-electrolyte(s) Na2CO3(aq) + 2 HC2H3O2(aq) ® 2 NaC2H3O2(aq) + CO2(g) + H2O(l) sol. salt weak acid sol. salt nonelectrolyte 2Na+(aq) + CO32−(aq) + 2HC2H3O2(aq) ® 2Na+(aq) + 2C2H3O2−(aq) + CO2(g) + H2O(l) NIE: CO32−(aq) + 2HC2H3O2(aq) ® 2C2H3O2−(aq) + CO2(g) + H2O(l) 16

Write the ionic and net ionic equation involving weak or non-electrolyte(s) NH4OH(aq) + HC2H3O2(aq) ® NH4C2H3O2(aq) + H2O(l) weak base weak acid sol. salt nonelectrolyte NH4OH(aq) + HC2H3O2 (aq) ® C2H3O2−(aq) + NH4+(aq) + H2O(l) NIE: no spectator ions, same as Complete Ionic Equations 17

Practice – Write the ionic and net ionic equation K2CO3(aq) + 2HC2H3O2(aq) ® H2O(l) + CO2(g) + 2KC2H3O2(aq) 2HI(aq) + BaSO3(s) ® BaI2(aq) + H2O(l) + SO2(g) BaBr2(aq) + 2AgNO3(aq) ® 2AgBr(s) + Ba(NO3)2(aq) 2 NH4OH(aq) + CuSO4(aq) ® Cu(OH)2(s) + (NH4)2SO4(aq) 18

More Practice – Convert and Complete, then Write the ionic and net ionic equation sulfuric acid + ammonium hydroxide  aluminum acetate + ammonium hydroxide  iron(II) sulfite + acetic acid  scandium(III) hydroxide + acetic acid  19

More Practice: Write and Balance the Ionic and Net Ionic Equation in aqueous solution from Word Equation hydrobromic acid + zinc metal  zinc bromide + hydrogen gas chlorine gas + water  hydrochloric acid + hypochlorous acid (as a weak acid) copper + iron(III) nitrate  iron(II) nitrate + copper(II) nitrate acetic acid + magnesium metal  magnesium acetate + hydrogen gas 20

Example–Ionic and net ionic equation NOTE: ONLY soluble salts, strong acids, and strong bases forms ions 2HNO3(aq) + Ca(OH)2(s) ® 2 H2O(l) + Ca(NO3)2(aq) Forms Ions? ______ _____ _____ ________ Ionic equation: Spectator ions? NIE: 2H+(aq) + Ca(OH)2(s) ® 2 H2O(l) + Ca2+(aq) 21

Practice –ionic equation ONLY soluble salts, strong acids, and strong bases forms ions Na2CO3(aq) + 2 HCl(aq) ® 2 NaCl(aq) + CO2(g) + H2O(l) sol. salt sol.acid sol. salt nonelectrolyte 2Na+(aq) + CO32−(aq) + 2H+(aq) + 2Cl−(aq) ® 2Na+(aq) + 2Cl−(aq) + CO2(g) + H2O(l) NIE: CO32−(aq) + 2 H+(aq) ® CO2(g) + H2O(l) 22

Practice – Write the ionic and net ionic equation K2CO3(aq) + 2 AgNO3(aq) ® 2 KNO3(aq) + Ag2CO3(s) sol. salt sol.salt sol. salt insoluble salt 2K+(aq) + CO32−(aq) + 2Ag+(aq) + 2NO3−(aq) ® 2K+(aq) + 2NO3−(aq) + Ag2CO3(s) NIE: 2 Ag+(aq) + CO32−(aq) ® Ag2CO3(s) 23

Write the ionic and net ionic equation involving weak or non-electrolyte(s) Na2CO3(aq) + 2 HC2H3O2(aq) ® 2 NaC2H3O2(aq) + CO2(g) + H2O(l) sol. salt weak acid sol. salt nonelectrolyte 2Na+(aq) + CO32−(aq) + 2HC2H3O2(aq) ® 2Na+(aq) + 2C2H3O2−(aq) + CO2(g) + H2O(l) NIE: CO32−(aq) + 2HC2H3O2(aq) ® 2C2H3O2−(aq) + CO2(g) + H2O(l) 24

Write the ionic and net ionic equation involving weak or non-electrolyte(s) NH4OH(aq) + HC2H3O2(aq) ® NH4C2H3O2(aq) + H2O(l) weak base weak acid sol. salt nonelectrolyte NH4OH(aq) + HC2H3O2 (aq) ® C2H3O2−(aq) + NH4+(aq) + H2O(l) NIE: no spectator ions, same as Complete Ionic Equations 25